Journey-To-Work Trends in the United States and its Major Metropolitan Areas 1960-1990
FHWA-EP-03-058
June 2003
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JOURNEY-TO-WORK TRENDS IN THE UNITED STATES
AND ITS MAJOR METROPOLITAN AREAS, 1960-1990
U.S. Department of Transportation
Research and Special Programs Administration
John A. Volpe National Transportation Systems Center
Cambridge, MA
Prepared for
U.S. Department of Transportation
Federal Highway Administration
Office of Highway Information Management
Washington, D.C.
FINAL REPORT
PREFACE/ACKNOWLEDGEMENTS
The work was supported by a project plan agreement between the
Federal Highway Administration, Office of Highway Information
Management, and the Volpe National Transportation Systems Center.
We thank the following individuals who offered guidance, support
and special services during the course of the project: Alan Pisarski,
James J. McDonnell, Matthew Rabkin, and Jeffrey Turner. We also thank
the Journey to Work and Migration Branch of the Bureau of the Census.
Special appreciation goes to Anne McEwan who provided exceptional
editorial and production support during the final draft.
NOTICE
This document is disseminated under the sponsorship of the Department
of Transportation in the interest of information exchange. The United
States Government assumes no liability for its contents or use
thereof.
iv
TABLE OF CONTENTS
EXECUTIVE SUMMARY
Thirty Year Trends, 1960-1990 . . . . . . . . . . . . . . . . .ES-1
Population and Workers . . . . . . . . . . . . . . . . . . .ES-1
Commuting. . . . . . . . . . . . . . . . . . . . . . . . . .ES-2
Household Vehicles . . . . . . . . . . . . . . . . . . . . .ES-2
Ten Year Trends, 1980-1990. . . . . . . . . . . . . . . . . . .ES-3
Population and Workers . . . . . . . . . . . . . . . . . . .ES-3
Commuting. . . . . . . . . . . . . . . . . . . . . . . . . .ES-3
Household Vehicles . . . . . . . . . . . . . . . . . . . . .ES-3
Geographic Revisions in Metropolitan Areas. . . . . . . . . . .ES-4
CHAPTER 1. INTRODUCTION
An Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Background. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Guide to Using the Report . . . . . . . . . . . . . . . . . . . 1-2
Cautions on Using Data in the Tables . . . . . . . . . . . . 1-2
Report Organization. . . . . . . . . . . . . . . . . . . . . 1-4
Sources of Data . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Limitations and Accuracy of the Data . . . . . . . . . . . . 1-5
Geography Considerations. . . . . . . . . . . . . . . . . . . . 1-5
Definition of Metropolitan Area. . . . . . . . . . . . . . . 1-5
Revisions to Geographic Boundaries . . . . . . . . . . . . . 1-6
New England. . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Data Definitions. . . . . . . . . . . . . . . . . . . . . . . . 1-7
Urban and Rural. . . . . . . . . . . . . . . . . . . . . . . 1-7
Household. . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Income of Households and Median Income . . . . . . . . . . . 1-9
Vehicles Available . . . . . . . . . . . . . . . . . . . . . 1-9
Employment Status. . . . . . . . . . . . . . . . . . . . . . 1-9
Place of Work. . . . . . . . . . . . . . . . . . . . . . . .1-10
Means of Transportation. . . . . . . . . . . . . . . . . . .1-12
Private Vehicle Occupancy. . . . . . . . . . . . . . . . . .1-12
Time Leaving Home to Go to Work. . . . . . . . . . . . . . .1-13
Travel Time to Work. . . . . . . . . . . . . . . . . . . . .1-13
CHAPTER 2. NATIONAL SUMMARY
Commuting Indicators. . . . . . . . . . . . . . . . . . . . . . 2-1
Thirty Year Trends . . . . . . . . . . . . . . . . . . . . . 2-1
Ten Year Trends. . . . . . . . . . . . . . . . . . . . . . . 2-4
v
TABLE OF CONTENTS (Cont.)
Household Formations . . . . . . . . . . . . . . . . . . . . 2-7
Urban Populations. . . . . . . . . . . . . . . . . . . . . . 2-7
Growth in the Number of Workers. . . . . . . . . . . . . . . 2-7
Workers per Household. . . . . . . . . . . . . . . . . . . .2-11
Density Indicators . . . . . . . . . . . . . . . . . . . . .2-11
Choice of Mode to Work. . . . . . . . . . . . . . . . . . . . .2-13
Driving Alone. . . . . . . . . . . . . . . . . . . . . . . .2-13
Carpooling . . . . . . . . . . . . . . . . . . . . . . . . .2-13
Public Transit . . . . . . . . . . . . . . . . . . . . . . .2-13
Walking to Work. . . . . . . . . . . . . . . . . . . . . . .2-15
Working at Home. . . . . . . . . . . . . . . . . . . . . . .2-15
Travel Time . . . . . . . . . . . . . . . . . . . . . . . . . .2-15
Time Leaving Home. . . . . . . . . . . . . . . . . . . . . .2-15
Total Vehicles and Vehicles Per Household . . . . . . . . . . .2-16
Zero Vehicle Households. . . . . . . . . . . . . . . . . . .2-16
One Vehicle Households . . . . . . . . . . . . . . . . . . .2-17
Two Vehicle Households . . . . . . . . . . . . . . . . . . .2-17
Three or More Vehicle Households . . . . . . . . . . . . . .2-17
CHAPTER 3. DEMOGRAPHIC CHARACTERISTICS
Population: Areawide, Central County, and Suburban
County. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Comparative Growth Rates in Central Counties
and Suburban Counties. . . . . . . . . . . . . . . . . . . . 3-1
Household Formation and Size . . . . . . . . . . . . . . . . 3-8
Urban Populations. . . . . . . . . . . . . . . . . . . . . . 3-8
Household Income . . . . . . . . . . . . . . . . . . . . . .3-14
CHAPTER 4. CHARACTERISTICS OF THE WORK TRIP: WORKER RESIDENCES,
PLACES OF WORK, COMMUTER FLOWS, AND TRAVEL TIMES
Characteristics of Workers. . . . . . . . . . . . . . . . . . . 4-1
Growth in the Number of Workers. . . . . . . . . . . . . . . 4-1
The Rise in Workers to Total Population. . . . . . . . . . . 4-2
The Male/Female Distribution of Workers. . . . . . . . . . . 4-2
Workers per Household and Workers per Family . . . . . . . .4-12
Workers by Place of Residence and Place of Work . . . . . . . .4-14
Workers Living in Central Counties . . . . . . . . . . . . .4-15
Workers Living in Suburban Counties. . . . . . . . . . . . .4-20
Jobs to Workers in Central Counties. . . . . . . . . . . . .4-20
vi
TABLE OF CONTENTS (Cont.)
Commuter Flows and Travel Times . . . . . . . . . . . . . . . .4-20
Intracounty and Intercounty Commuting Trends . . . . . . . .4-20
Commuting Flows. . . . . . . . . . . . . . . . . . . . . . .4-25
Travel Time. . . . . . . . . . . . . . . . . . . . . . . . .4-36
Time Leaving Home to Go to Work. . . . . . . . . . . . . . .4-36
CHAPTER 5. MEANS OF JOURNEY TO WORK
The Use of Privately Owned Vehicles for Commuting . . . . . . . 5-1
Commuting Shares Accounted for by Privately
Owned Vehicles . . . . . . . . . . . . . . . . . . . . . . . 5-1
Privately Owned Vehicles - Drivers, Passengers
and Occupancy Rates. . . . . . . . . . . . . . . . . . . . . 5-4
Individual Modal Trends . . . . . . . . . . . . . . . . . . . . 5-4
Driving Alone. . . . . . . . . . . . . . . . . . . . . . . . 5-4
Carpooling . . . . . . . . . . . . . . . . . . . . . . . . .5-14
Public Transit (Bus and Rail). . . . . . . . . . . . . . . .5-14
Working at Home. . . . . . . . . . . . . . . . . . . . . . .5-21
Bicycling and Walking to Work. . . . . . . . . . . . . . . .5-25
CHAPTER 6. VEHICLE OWNERSHIP AND AVAILABILITY
Trends in Household Vehicle Ownership . . . . . . . . . . . . . 6-1
Average Number of Vehicles per Household . . . . . . . . . . 6-7
Zero Vehicle Households. . . . . . . . . . . . . . . . . . . 6-7
One Vehicle Households . . . . . . . . . . . . . . . . . . . 6-7
Two Vehicle Households . . . . . . . . . . . . . . . . . . . 6-7
Three or More Vehicle Households . . . . . . . . . . . . . . 6-9
CHAPTER 7. SELECTED CHANGES BASED ON 1992 GEOGRAPHIC REDEFINITION
Geographic Boundary Changes . . . . . . . . . . . . . . . . . . 7-1
Changes in Total Areawide Population and
Population Density . . . . . . . . . . . . . . . . . . . . . 7-1
Changes in Total Areawide Workers. . . . . . . . . . . . . . 7-5
Changes in Total Areawide Vehicle Populations. . . . . . . . 7-5
Changes in Land Area . . . . . . . . . . . . . . . . . . . . 7-5
PROFILES. U.S. AND METROPOLITAN AREA MAPS AND STATISTICAL PROFILES
National Summary Statistics . . . . . . . . . . . . . . . . . . P-5
New York-Northern New Jersey- Long Island, NY-NJ CMSA . . . . . P-7
Los Angeles-Anaheim-Riverside, CA CMSA. . . . . . . . . . . . . P-9
vii
TABLE OF CONTENTS (Cont.)
Chicago-Gary-Lake County, IL-IN-WI CMSA . . . . . . . . . . . .P-11
San Francisco-Oakland-San Jose, CA CMSA . . . . . . . . . . . .P-13
Philadelphia-Wilmington-Trenton, PA-NJ-DE-MD CMSA . . . . . . .P-15
Detroit-Ann Arbor, MI CMSA. . . . . . . . . . . . . . . . . . .P-17
Boston-Lawrence-Salem, MA-NH CMSA . . . . . . . . . . . . . . .P-19
Washington, DC-MD-VA MSA. . . . . . . . . . . . . . . . . . . .P-21
Dallas-Fort Worth, TX CMSA. . . . . . . . . . . . . . . . . . .P-23
Houston-Galveston-Brazoria, TX CMSA . . . . . . . . . . . . . .P-25
Miami- Fort Lauderdale, FL CMSA . . . . . . . . . . . . . . . .P-27
Atlanta, GA MSA . . . . . . . . . . . . . . . . . . . . . . . .P-29
Cleveland-Akron-Lorain, OH CMSA . . . . . . . . . . . . . . . .P-31
Seattle-Tacoma, WA CMSA . . . . . . . . . . . . . . . . . . . .P-33
San Diego, CA MSA . . . . . . . . . . . . . . . . . . . . . . .P-35
Minneapolis-St. Paul, MN-WI MSA . . . . . . . . . . . . . . . .P-37
St. Louis, MO-IL MSA. . . . . . . . . . . . . . . . . . . . . .P-39
Baltimore, MD MSA . . . . . . . . . . . . . . . . . . . . . . .P-41
Pittsburgh-Beaver Valley, PA CMSA . . . . . . . . . . . . . . .P-43
Phoenix, AZ MSA . . . . . . . . . . . . . . . . . . . . . . . .P-45
Tampa-St. Petersburg-Clearwater, FL MSA . . . . . . . . . . . .P-47
Denver-Boulder, CO CMSA . . . . . . . . . . . . . . . . . . . .P-49
Cincinnati-Hamilton, OH-KY-IN CMSA. . . . . . . . . . . . . . .P-51
Milwaukee-Racine, WI CMSA . . . . . . . . . . . . . . . . . . .P-53
Kansas City, MO-KS MSA. . . . . . . . . . . . . . . . . . . . .P-55
Sacramento, CA MSA. . . . . . . . . . . . . . . . . . . . . . .P-57
Portland-Vancouver, OR-WA . . . . . . . . . . . . . . . . . . .P-59
Norfolk-Virginia Beach-Newport News, VA MSA . . . . . . . . . .P-61
Columbus, OH MSA. . . . . . . . . . . . . . . . . . . . . . . .P-63
San Antonio, TX MSA . . . . . . . . . . . . . . . . . . . . . .P-65
Indianapolis, IN MSA. . . . . . . . . . . . . . . . . . . . . .P-67
New Orleans, LA MSA . . . . . . . . . . . . . . . . . . . . . .P-69
Buffalo-Niagara Falls, NY CMSA. . . . . . . . . . . . . . . . .P-71
Charlotte-Gastonia-Rock Hill, NC-SC MSA . . . . . . . . . . . .P-73
Providence-Pawtucket-Fall River, RI-MA CMSA . . . . . . . . . .P-75
Hartford-New Britain-Middletown, CT CMSA. . . . . . . . . . . .P-77
Orlando, FL MSA . . . . . . . . . . . . . . . . . . . . . . . .P-79
Salt Lake City-Ogden, UT CMSA . . . . . . . . . . . . . . . . .P-81
Rochester, NY MSA . . . . . . . . . . . . . . . . . . . . . . .P-83
APPENDIX A. Changes in MSA/CMSA County List, 1974-1983. . . . . . A-1
APPENDIX B. List of all Counties in Metropolitan Areas -
1983 Geography . . . . . . . . . . . . . . . . . . . . B-1
viii
LIST OF TABLES
EXECUTIVE SUMMARY
CHAPTER 1. INTRODUCTION
1-1 Listing of Metropolitan Areas With Over One Million
Inhabitants in 1990 (Listed numerically by population
rank, and alphabetically). . . . . . . . . . . . . . . . . . 1-3
1-2 Effect of 1983 OMB Revisions on Geographies of 1990
Metropolitan Areas with Over One Million Inhabitants . . . . 1-8
CHAPTER 2. NATIONAL SUMMARY
2-1 Journey-to-Work Comparisons, National Totals,
1960-1990. . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2-2 National Trends 1960-1990 Factors, U.S. Totals
Compared to Metropolitan Areas With Over One Million
Inhabitants. . . . . . . . . . . . . . . . . . . . . . . . . 2-3
2-3 Ten Year Trends in Journey-to-Work Factors, U.S.
Totals Compared to Metropolitan Areas With Over One
Million Inhabitants (based on 1983 geography). . . . . . . . 2-5
2-4 Journey-to-Work Profile: National Summary Statistics
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
2-5 Selected Demographic and Commuting Comparisons, U.S.
and Large Metropolitan Areas, 1990 . . . . . . . . . . . . . 2-7
2-6 Indicators, Trends, and Factsheet for Journey-to-Work
Patterns, 1980-1990. . . . . . . . . . . . . . . . . . . . . 2-8
2-7 Journey to Work, 1990, Maximums and Minimums by State. . . . 2-9
2-8 Journey to Work, 1990, Maximums and Minimums by
Metropolitan Area. . . . . . . . . . . . . . . . . . . . . .2-10
2-9 Labor Force Participation Rates by Sex, Percentages,
1960-1990. . . . . . . . . . . . . . . . . . . . . . . . . .2-11
2-10 Departure Times to Work, U.S. and Metropolitan Area
Comparisons, 1990. . . . . . . . . . . . . . . . . . . . . .2-15
CHAPTER 3. DEMOGRAPHIC CHARACTERISTICS
3-1 Population (Areawide, Central and Suburban Counties)
1960-1980. . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3-1A Population (Areawide, Central and Suburban Counties)
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
3-2 Fastest and Slowest Growing Metropolitan Areas, Percent
Changes by Decade. . . . . . . . . . . . . . . . . . . . . . 3-5
3-3 Fastest Growing Suburban Counties in Large
U.S. Metropolitan Areas, 1960-1980 and 1980-1990 . . . . . . 3-5
3-4 Central County Population, 1960-1990 . . . . . . . . . . . . 3-9
3-5 Relationship of Central County to Areawide Population,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . .3-11
3-6 Demographic Ratios and Urban/Rural Population
Percentages, 1990. . . . . . . . . . . . . . . . . . . . . .3-15
3-7 Median Household Income and Percent of Households
in Income Intervals, Thirty-Nine Metropolitan Areas,
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-16
ix
LIST OF TABLES (Cont.)
CHAPTER 4. CHARACTERISTICS OF THE WORK TRIP: WORKER RESIDENCES,
PLACES OF WORK, COMMUTER FLOWS AND TRAVEL TIMES
4-1 Worker Comparisons, U.S. and Thirty-Nine Metropolitan
Areas, 1990. . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4-2 Workers by Place of Residence
(Areawide, Central, and Suburban Counties) 1960-1980 . . . . 4-4
4-2A Workers by Place of Residence
(Areawide, Central, and Suburban Counties) 1980-1990 . . . . 4-7
4-3 Workers As a Percent of Population, 1960-1980. . . . . . . . 4-8
4-3A Workers As a Percent of Population, 1980-1990. . . . . . . . 4-9
4-4 Workers by Gender, 1960-1980 . . . . . . . . . . . . . . . .4-10
4-4A Workers by Gender, 1980-1990 . . . . . . . . . . . . . . . .4-11
4-5 Workers per Household, 1980 and 1990, for Large
Metropolitan Areas . . . . . . . . . . . . . . . . . . . . .4-14
4-6 Workers by County of Residence, Large Metropolitan
Areas, 1960-1990 . . . . . . . . . . . . . . . . . . . . . .4-15
4-7 Central County Workers, 1960-1990. . . . . . . . . . . . . .4-17
4-8 Place of Work, Workers Living in Central Counties,
1980 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-18
4-8A Place of Work, Workers Living in Central Counties,
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-19
4-9 Place of Work, Workers Living in Suburban Counties,
1980 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-23
4-9A Place of Work, Workers Living in Suburban Counties,
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-24
4-10 Workers Living & Working in the Same County,
1960-1980. . . . . . . . . . . . . . . . . . . . . . . . . .4-29
4-10A Workers Living & Working in the Same County,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . .4-30
4-11 Workers Living & Working in Different Counties,
1960-1980. . . . . . . . . . . . . . . . . . . . . . . . . .4-31
4-11A Workers Living & Working in Different Counties,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . .4-32
4-12 Journey-to-Work Flows, Share of Commuters, 1980 and
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-34
4-13 Journey-to-Work Flows, Mean Travel Times and
Percent Changes, 1980 and 1990 . . . . . . . . . . . . . . .4-38
4-14 Travel Time Intervals to Work, Percent Distribution
(in minutes), 1990 . . . . . . . . . . . . . . . . . . . . .4-39
4-15 Departure Time Intervals for Work Trips, U.S. and
Large Metropolitan Areas, Percentage Distributions,
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-40
4-16 Time Leaving Home to Go to Work, 1990. . . . . . . . . . . .4-41
CHAPTER 5. MEANS OF JOURNEY TO WORK
5-1 Workers Use of Privately Owned Vehicles, 1960-1980 . . . . . 5-2
5-1A Workers Use of Privately Owned Vehicles,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
5-2 Workers Travel by Privately Owned Vehicles, Percent
Change Between 1960-1980 . . . . . . . . . . . . . . . . . . 5-5
5-2A Workers Travel by Privately Owned Vehicles, Percent
Change Between 1980-1990 . . . . . . . . . . . . . . . . . . 5-6
5-3 Privately Owned Vehicle Occupancy, 1970-1980 . . . . . . . . 5-7
5-3A Privately Owned Vehicle Occupancy, 1980-1990 . . . . . . . . 5-8
5-4 Privately Owned Vehicle Occupancy, Central and
Suburban Counties, 1990. . . . . . . . . . . . . . . . . . . 5-9
5-5 Privately Owned Vehicle Drivers and Passengers,
Percent Change Between 1980-1990 . . . . . . . . . . . . . .5-10
x
LIST OF TABLES (Cont.)
5-6 Journey to Work by Mode, 1980. . . . . . . . . . . . . . . .5-11
5-6A Journey to Work by Mode, 1990. . . . . . . . . . . . . . . .5-12
5-7 Journey-to-Work Mode Share, 1990 . . . . . . . . . . . . . .5-13
5-8 Journey to Work by Vehicle Pools, 1990 . . . . . . . . . . .5-16
5-9 Journey to Work by Bus, Percent Change Between
1960-1980. . . . . . . . . . . . . . . . . . . . . . . . . .5-19
5-9A Journey to Work by Public Transit, Percent Change
Between 1980-1990. . . . . . . . . . . . . . . . . . . . . .5-20
CHAPTER 6. VEHICLE OWNERSHIP AND AVAILABILITY
6-1 Households by Vehicle Availability, 1980-1990. . . . . . . . 6-2
6-2 Households by Vehicle Availability, Percent Change
1960-1980. . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
6-2A Households by Vehicle Availability, Percent Change
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
CHAPTER 7. SELECTED CHANGES BASED ON 1992 GEOGRAPHIC REDEFINITION
7-1 Changes in Metropolitan Areas as a Result of the 1992
OMB Revision . . . . . . . . . . . . . . . . . . . . . . . . 7-2
7-2 1990 Population, 1983 & 1992 Geography Definition. . . . . . 7-3
7-3 1990 Worker Population, 1983 & 1992 Geography
Definition . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
7-4 1990 Workers as a Percent of Population, 1983 & 1992
Geography Definition . . . . . . . . . . . . . . . . . . . . 7-6
7-5 1990 Vehicle Availability, 1983 & 1992 Geography
Definition . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
7-6 1990 Land Area (in Square Miles), 1983 & 1992
Geography Definition . . . . . . . . . . . . . . . . . . . .7-10
7-7 1990 Vehicle Population, 1983 & 1992 Geography
Definition . . . . . . . . . . . . . . . . . . . . . . . . .7-11
7-8 1990 Population Density Per Square Mile, 1983 & 1992
Geography Definition . . . . . . . . . . . . . . . . . . . .7-12
7-9 1990 Worker Density Per Square Mile, 1983 & 1992
Geography Definition . . . . . . . . . . . . . . . . . . . .7-13
7-10 1990 Vehicle Density Per Square Mile, 1983 & 1992
Geography Definition . . . . . . . . . . . . . . . . . . . .7-14
PROFILES. U.S. AND METROPOLITAN AREA MAPS AND STATISTICAL PROFILES
P-1 Listing of Metropolitan Areas With Over One Million
Inhabitants in 1990. . . . . . . . . . . . . . . . . . . . . P-2
xi
LIST OF FIGURES
EXECUTIVE SUMMARY
ES-1 Total Population and Full-Time Workers 1960 and 1990 . . . .ES-1
ES-2 Total Workers by Sex 1960 and 1990 . . . . . . . . . . . . .ES-1
ES-3 Total Worker Commutes by Mode 1960 and 1990. . . . . . . . .ES-2
ES-4 Total Households by Number of Household Vehicles,
1960 and 1990. . . . . . . . . . . . . . . . . . . . . . . .ES-2
ES-5 Effect of Geographic Revision on Total Population of
Metropolitan Areas . . . . . . . . . . . . . . . . . . . . .ES-4
CHAPTER 1. INTRODUCTION
1-1 Effect of Geographic Revisions on Suburban Population,
Thirty-Nine Metropolitan Areas, 1960-1990. . . . . . . . . . 1-8
CHAPTER 2. NATIONAL SUMMARY
2-1 Selected Density Indicators, 1990 - 39 Metropolitan
Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12
2-2 Means of Journey to Work, 1990 - National and
Metropolitan Area Totals . . . . . . . . . . . . . . . . . .2-14
CHAPTER 3. DEMOGRAPHIC CHARACTERISTICS
3-1 Central County Comparisons, 1990 - Percent
Areawide Population & Land . . . . . . . . . . . . . . . . . 3-7
3-2 Effect of 1983 Geographic Revision on Area Population. . . . 3-6
3-3 Changes in Central County Population, 1960-1990. . . . . . .3-10
3-4 Central County Share of Area Population - Percent
Change 1980-1990 . . . . . . . . . . . . . . . . . . . . . .3-12
3-5 1990 Household Ratios. . . . . . . . . . . . . . . . . . . .3-13
CHAPTER 4. CHARACTERISTICS OF THE WORK TRIP: WORKER RESIDENCES,
PLACES OF WORK, COMMUTER FLOWS, AND TRAVEL TIMES
4-1 Percent Workers to Total Population, 1960-1990 . . . . . . . 4-3
4-2 Male/Female Worker Ratios, 1960-1990 . . . . . . . . . . . . 4-6
4-3 Workers Per Family - Percentage Distributions
(1989 Data). . . . . . . . . . . . . . . . . . . . . . . . .4-13
4-4 Workers Residing in Central County - Work Location -
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-16
4-5 Workers Residing in Suburban Counties Work Location -
1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-21
4-6 Central County Jobs to Workers, 1990 . . . . . . . . . . . .4-22
4-7 Workers Living & Working in Same County - Percent
Change 1960-1990 . . . . . . . . . . . . . . . . . . . . . .4-26
4-8 Workers Living & Working in Different Counties -
Percent Change 1960-1990 . . . . . . . . . . . . . . . . . .4-27
4-9 Commuter Flows - Percent Distribution, 1990. . . . . . . . .4-28
4-10 Mean Travel Time to Work, 1980 and 1990. . . . . . . . . . .4-37
xii
LIST OF FIGURES (Cont.)
CHAPTER 5. MEANS OF JOURNEY TO WORK
5-1 Drive Alone vs. Vehicle Pool Trips - Percent of
All Work Trips, 1990 . . . . . . . . . . . . . . . . . . . .5-15
5-2 Vehicle Pools in Commuting, 1990 - Percent of All
Private Vehicle Trips. . . . . . . . . . . . . . . . . . . .5-18
5-3 Commuting by Bus/Streetcar to Work - Percent Change,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . .5-22
5-4 Commuting by Bus/Streetcar to Work - Percent Change,
1960-1990. . . . . . . . . . . . . . . . . . . . . . . . . .5-23
5-5 Commuting by Rail or Subway to Work - Percent Change,
1960-1990. . . . . . . . . . . . . . . . . . . . . . . . . .5-24
5-6 Work at Home, 1980-1990 - Number of Workers and
Percent Change . . . . . . . . . . . . . . . . . . . . . . .5-26
5-7 Walk and Bike to Work, 1990 - Percent Distribution . . . . .5-27
CHAPTER 6. VEHICLE OWNERSHIP AND AVAILABILITY
6-1 Total Vehicles and Population - Percent Change,
1980-1990. . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
6-2 Vehicles Per Square Mile, 1990 . . . . . . . . . . . . . . . 6-4
6-3 Zero Vehicle Households, 1980-1990 - Percent Change,
Central and Suburban County. . . . . . . . . . . . . . . . . 6-8
6-4 Three+ Vehicle Households, 1980-1990 - Percent Change,
Central and Suburban County. . . . . . . . . . . . . . . . .6-10
xiii
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xiv
EXECUTIVE SUMMARY
How people in the United States travel to work is affected by
demographic and worker characteristics, the availability of
alternative modes of commuting, perceived travel time and the supply
and location of jobs. This report explores commuting behavior on both
a national and a metropolitan area basis from data drawn from the U.S.
Decennial Census. Topics covered in the report include: population
characteristics, characteristics of workers, mode choice for the
commute trip and vehicle ownership and availability, and the effect on
the data of geographic revisions. The thirty year trends from 1960-
1990 are observed, as well as the more recent trends over the ten
years from 1980-1990. Two levels of analysis are presented. First,
national level trends are looked at, followed by an analysis of trends
in large metropolitan areas.
Thirty Year Trends, 1960-1990
Population and Workers. Over the thirty year period from 1960-1990
the U.S. population increased 39% from 179 million to 249 million, and
the number of households increased 73% from 53 million in 1960 to 92
million in 1990. During this same period, however, household size
decreased from 3.33 persons per household to 2.63 persons per
household.
The number of workers from 1960-1990 increased 78%, from about 65
million to 115 million (Figure ES-1). This increase in the number of
workers is almost twice the rate of population growth. Much of the
increase can be attributed to increasing numbers of women in the
workforce. In 1960, women comprised only 32.3% of the workforce, but
by 1990 this number had jumped to 45.3% (Figure ES-2). Also of note
is that the percent of workers with jobs outside their county of
residence increased 200% between 1960 and 1990, while the percent of
central county commutes declined.
Metropolitan areas with populations over one million increased from
thirty-four areas in 1960 to thirty-nine areas in 1990. Population
within these metropolitan areas increased much more than the
Click HERE for graphic.
ES-1
national figures, growing from 77 million people in 1960 to 124
million people in 1990, a 60% increase. By definition, population is
much more dense in the metropolitan areas than in the U.S. as a whole,
with 664 persons per square mile in the former and only 70 persons per
square mile in the latter. A decrease in household size, much the
same as the national decrease, resulted in persons per household
dropping from 3.24 in 1960 to 2.65 in 1990.
In the thirty-nine metropolitan areas the number of workers
increased at a faster rate than nationally. The figures more than
doubled from 29 million workers in 1960 to almost 60 million workers
in 1990. Each successive decade from 1960 onward produced a 22%
average annual growth rate from 1960-1990. Nationally in 1990, there
were 33 workers per square mile, while in the metropolitan areas there
were 320 workers per square mile. The number of women in the
workforce in the metropolitan areas increased almost identically to
the national figures, from 33.6% to 45.6%.
Commuting. Private vehicle trips increased consistently as more
people began to drive alone to work. From 1960-1990, total workers
increased by 78%, while workers commuting by private vehicle rose from
43 million in 1960 to 101 million in 1990, or about 135.5%. By 1990,
workers commuting by private vehicle accounted for 88% of all commute
trips (Figure ES-3). Transit decreased from 7.8 million in 1960 to
5.9 million in 1990 as more and more people began to drive alone to
work. Departure times were spread over many hours, with most workers
departing between 7:00 A.M. and 8:29 A.M. An important external
factor affecting commuting behavior is increasing suburbanization of
the United States. Those workers whose jobs were located outside
their counties of residence rose from 9 million in 1960 to 27.5
million in 1990, a gain of 206%, the fastest rising segment of work
commuters.
In almost every instance from 1960-1990, private vehicles captured
increasingly larger shares of all metropolitan area work trips.
Indeed, private vehicle trips increased from 61% of all commute trips
in 1960 to 83% in 1990. In fourteen of the thirty-nine metropolitan
areas private vehicles accounted for over 90% of total 1990 commute
trips. Also in 1990, transit ridership in metropolitan areas was 9%,
while only 5.3% nationally.
Household Vehicles. Household vehicle growth was very strong,
almost tripling from 54.8 million in 1960 to 152.4 million in 1990.
In 1960, the average household had only one vehicle, but that figure
rose to 1.66 by 1990 as multiple vehicle households became the
majority. Similarly, the number of households with three or more
vehicles increased to 17% of all households or nearly 16 million in
1990, up from only 1.3 million in 1960, becoming the fastest growing
of all household types. Almost all the growth in vehicles has
occurred in households with two or more vehicles. These growth
patterns are illustrated in Figure ES-4. Additional factors affecting
household ownership of vehicles include the increase in average
vehicle age and the advent of smaller, more fuel efficient
Click HERE for graphic.
ES-2
automobiles. From 1960-1990 vehicles per household in the
metropolitan areas increased from 1.0 to 1.59, while vehicles per
person increased from 0.31 to 0.58. Overall, suburban counties had
higher growth rates in vehicles per household than central counties.
Ten Year Trends, 1980-1990
Population and Workers. In the ten years from 1980-1990 the U.S.
population increased 9.8%, from 227 million people to 248 million
people and the number of households increased 14% from 80 million to
92 million. Persons per household, continuing the trend from 1960
onward, declined 4.4% from 2.75 to 2.63. The number of workers
increased 19%, from 97 million to 115 million. Workers per household
in contrast, increased less than 5%, from 1.22 to 1.25. The
comparatively small increase in workers per household is explained by
the dramatic tandem drop in household size. Workers who worked in
their county of residence increased 25% from 1980-1990, while workers
who worked outside their county of residence increased almost 50%.
The population increased slightly faster in metropolitan areas than
in the U.S. as a whole, from 111 million in 1980 to 124 million in
1990. Persons per household in the thirty-nine metropolitan areas in
1990 ranged from a high of 3.04 in Salt Lake City to a low of 2.32 in
Tampa. The number of workers in the metropolitan areas also rose
slightly faster than the number of workers nationally, from 46 million
in 1980 to 59.7 million in 1990. The number of workers per household
rose from 1.18 in 1980 to 1.31 in 1990. Again, like the national
numbers listed above, this increase appears much less static in light
of decreasing household size. From 1980-1990, among the metropolitan
areas, the maximum number of workers per household was 1.52 in
Washington, D.C., while the minimum was in Tampa with 1.05. The
maximum number of workers as a percent of population was in
Washington, D.C. with 56.4%, while the minimum was in New Orleans with
41.5%.
Commuting. In 1980, 64% of all commuters drove alone to work; by
1990 the drive alone share had increased to 73%. This increase in the
rate of driving alone substantially affected other journey-to-work
modes. Transit use, for example, fell from 6.2% to 5.1% from 1980-
1990. The share of people walking to work decreased from 5.4 million
in 1980 to 4.5 million in 1990. Additionally, the percentage of
persons using carpools declined 32%. Time spent commuting has
increased slowly from 21.7 minutes in 1980 to 22.4 minutes in 1990.
Much of the gain in numbers of people driving alone from 1980 to
1990 came at the expense of carpooling, and to a lesser degree,
transit. Transit declined from 6.22% in 1980 to 5.12% in 1990.
Working at home showed an increase from 2.2 million in 1980 to 3.4
million in 1990. However, over the thirty years from 1960-1990
working at home experienced an overall 27% loss in share of commute
modes. Central county to central county and suburban county to same
suburban county commute trips composed the majority of trips for the
metropolitan areas in 1990. In 1990, workers in metropolitan areas
averaged 25.2 minutes commuting to their jobs.
Household Vehicles. The dramatic rise in vehicles per household
mentioned above halted and from 1980-1990 the number of vehicles per
household grew only 5%, from 1.61 in 1980 to 1.66 in 1990. Vehicles
per worker declined a small amount from 1.34 to 1.32. Between 1980
and 1990 zero vehicle households, as a percentage of all households,
declined by 11% while households with three or more vehicles remained
constant.
ES-3
The unprecedented growth in the number of vehicles per household
that occurred between 1960-1980 slowed (much like the figures for the
U.S. as a whole) from 1.52 in 1980 to 1.59 in 1990. From 1980-1990
seventeen central counties had declines in zero vehicle households and
thirty counties experienced growth in three or more vehicle
households. In 1990, Tampa and Sacramento, at 1.45 vehicles per
worker, tied for the maximum number, while New York City had the
minimum with 0.93 vehicles per worker.
Geographic Revisions in Metropolitan Areas
The Office of Management and Budget (OMB) periodically revises the
geographic boundaries of metropolitan areas, thus affecting data
comparisons for Census journey-to-work data. Figure ES-5 shows the
effect of the 1983 revision on total population in large metropolitan
areas. The net effect was to increase area population counts. As a
result of the revision, population in metropolitan areas changed in
1980 from 102 million to 110.7 million. The bulk of this Report
includes tables using the 1974 and 1983 OMB definitions. In 1992, OMB
again updated the definition of metropolitan areas. The effect of
this was a general expansion in the land area of the thirty-nine
metropolitan areas. Chapter 7 includes tables comparing figures using
the 1983 and 1992 OMB definitions. The expansion affects the
demographic characteristics of the land area in two ways. First,
population in the metropolitan areas increased slightly. Second,
population density declined as larger, less populated counties were
added to the boundaries of the metropolitan areas.
Click HERE for graphic.
ES-4
Chapter 1
INTRODUCTION
Chapter 1 provides an overview and reviews the background of this
report. It addresses issues of geographic revision, the sources and
definitions of data, and the limitations of the data. Guidance is
provided on using and interpreting the data tables found in the
report. The organization of the report is then outlined and
discussed.
An Overview
This report documents the changes that occurred nationwide between
1960 and 1990 in journey-to-work demographic characteristics,
geographic flows, mode of travel to work, vehicle availability, and
other related indicators of commuting activity by U.S. workers.1
Thirty years ago, most commuter trips were traditional, home-to-work,
suburb-to-central city trips. A journey to work in 1990 is more
likely to include side trips for day care, for convenience shopping,
or some other purpose aside from getting to or from work. It is also
more likely to occur entirely within suburban counties. In this
report, particular emphasis is placed on the 1980-1990 period, where
rapidly changing socioeconomic factors may help to explain various
trends that occurred.
Most of the data used in this report are from the 1990 Census of
Population and Housing, Summary Tape File (STF) 3, and earlier
editions of the Census of Population and Housing.
In the chapters that follow, more detailed information is provided
for each of the thirty-nine metropolitan areas having over one million
residents as reported in the 1990 Census and defined by the Office of
Management and Budget. The general structure is to report information
at three levels: 1) metropolitan areawide data, 2) central county
data, and 3) suburban county data. By subject area, the report looks
at population and households, worker characteristics, places of work
and residence, worker flows and travel times, mode of travel, and
vehicle availability.
Background
In 1986, the FHWA published the report Journey-to-Work Trends Based
on 1960, 1970, and 1980 Decennial Censuses2 (from now on called the
Trends report). The report was prepared for use by policy makers,
program managers, and researchers in the analysis of the highway and
transportation system. The design and content of the report were
guided by a special task force of the TRB Committee on Data Collection
and Information Systems. Material in the FHWA report was the basis of
the highly regarded Commuting in America3 report.
____________________
1The present report updates and expands upon an earlier report:
Briggs, D., Pisarski, A. and McDonnell, J. "Journey-to-Work-Trends
Based on 1960, 1970 and 1980 Decennial Censuses" (U.S. DOT/FHWA, July
1986).
2Briggs, D., Pisarski, A. and McDonnell, J. "Journey-to-
Work Trends Based on the 1;960, 1970 and 1980 Decennial Censuses"
(U.S. DOT/FHWA. July, 1986)
3Pisarski, A. "Commuting in America" (Eno Foundation, 1987)
1-1
A DOT Working Group on Journey to Work was established in 1992 to
guide the writing of the present report. The objective of this report
was to update and expand the information in the Trends report. The
Trends report covered thirty-four metropolitan areas. Due to changes
in population, the list of new areas has grown to thirty-nine areas,
encompassing six additions and one deletion (Dayton/Springfield).4
Table 1-1 lists the thirty-nine metropolitan areas included in this
report. The profile numbers match 1990 population ranks while the
codes reference the graphs used in this report.
Guide to Using the Report
Cautions on Using Data in the Tables. The tables in chapters two
through six depict the U.S. and its thirty-nine metropolitan areas
with over one million inhabitants in 1990. At the bottom of each
table, totals are provided. Because there are occasional missing
entries for metropolitan areas, readers should exercise caution when
comparing the totals. This is especially so when comparing entries
from the 1960-1980 and 1980-1990 periods, because the geography and
metropolitan areas both change across the periods. Table P-1 in the
Profiles section presents national level totals for many data items,
and readers may wish to refer to these when making specific
metropolitan area comparisons. Other details to bear in mind include:
- Metropolitan Areas: In comparing data from 1960-1980 with data
from 1990, readers should note that the two groups of
metropolitan areas over one million are not in direct
correspondence. The 1960-1980 group contains thirty-four areas,
while the 1980-1990 group has thirty-nine areas.
- Totals: Column totals reflect only metropolitan areas for which
data were obtainable for all years represented on the table.
Totals are provided only for the convenience of readers, and do
not necessarily suggest all activity for metropolitan areas over
one million. Missing data should be noted before using totals.
- Percent Changes: All totals for percent changes reflect only
those metropolitan areas for which data were obtainable. Thus,
any missing observations were first excluded from calculations.
____________________
4Six new metropolitan areas were added in 1990. These areas and their
central counties are:
Metropolitan Area Central County
Norfolk, VA Norfolk City, VA
Charlotte NC/SC Mecklenberg County, NC
Hartford, CT Hartford City, CT
Orlando, FL Orange County, FL
Salt Lake City, UT Salt Lake County, FL
Rochester, NY Monroe County, NY
1-2
Table 1-1. Listing of Metropolitan Areas With Over One Million
Inhabitants in 1990 (Listed numerically by population
rank, and alphabetically)
Click HERE for graphic.
1-3
Report Organization. The report provides information for each of
the thirty-nine metropolitan areas having over one million residents
as defined by the 1990 Census figures. The general structure is to
report information at three levels: 1) metropolitan areawide data, 2)
central county data, and 3) suburban county data. In terms of broad
themes, the report looks at population and households, worker
characteristics, places of work and residence, worker flows and travel
times, mode of travel, and vehicle availability.
Chapter 2 documents national changes that occurred between 1960 and
1990 in journey-to-work demographic characteristics, geographic flows,
mode of travel to work, vehicle availability, and other related
indicators of commuting activity by U.S. workers. Particular emphasis
is placed on the years from 1980-1990, a decade of rapidly changing
socioeconomic factors.
Chapter 3 describes population characteristics within the thirty-
nine metropolitan areas, including trends for central and suburban
counties. The effects of central county size and land area are
assessed, along with such items as household formation and size,
household income, and urban and rural residence. Some principal
themes that emerge from the analysis include declining household size,
rapid population growth in Sunbelt areas, and population growth in
suburban areas.
Chapter 4 describes characteristics of the work trip. The chapter
includes discussion and tables on residential and workplace location
based on central/suburban county definitions and the effect of
commuting flows and travel times. Also included is new data on time
leaving home to go to work.
Chapter 5 includes tables on mode choice for the commute trip.
Drive alone trips were foremost over the past 30 years, while losses
occurred in public transit, carpooling and even walking. There was
some growth in the number of people who work at home. Some factors
contributing to mode choice include increases in multipurpose trips,
the increase in women in the labor force, and the adoption of flexible
work hours by some companies.
Chapter 6 addresses household vehicle ownership and availability,
including vehicles per person and vehicles available per worker.
Nearly 80 million vehicles were located within the thirty-nine
metropolitan areas comprising the study group. Over the thirty-year
period, vehicles per household grew 60%, while vehicles per worker
increased by over 50%.
Chapter 7 documents the changes in geographic redefinition of the
metropolitan areas. In late 1992, the U.S. Office of Management and
Budget revised the geography of many metropolitan areas discussed in
this report. This chapter illustrates how the new geographic
boundaries affect some population, worker, and vehicle characteristics
described in earlier chapters of the report.
The Profiles section includes a map showing the geography, county
boundaries, and central cities of each metropolitan area. Also
provided are a one-page statistical profile sheet of 1990 data for
each metropolitan area and a profile of U.S. totals. Readers can
obtain local commuting and demographic statistics from these profiles.
Most of the data in these profiles are replicated in the topically
defined tables in the preceding chapters.
The Appendices provide details on additions and deletions of
counties that have resulted from geographic revisions.
1-4
Sources of Data
The Census Bureau distributes data from the 1990 Census of
Population and Housing in a series of Summary Tape Files (STF's).
There are four STF series at various levels of geographic detail. In
preparing this report, the STF 3A series was used. It includes sample
data weighted to represent the total population. In addition, the
file contains 100-percent counts and unweighted sample counts. It
contains characteristics similar in content to the 1980 STE but with
expanded detail. The STF 3A provides data for states and their sub-
areas in hierarchical sequence down to the block-group level. These
include county, county subdivision, place (or place part), census
tract/block numbering area (or part), and block group (or part).
Information was extracted from CD-ROMs and loaded onto a database
manager and spreadsheet software programs. When required, data for
earlier years were obtained directly from the Census Bureau or from
publications commonly available in libraries, such as the Census of
Population and Housing (CPH-L-80) data set.
Limitations and Accuracy of the Data. Because the geographic scale
of analysis is limited to counties in this report, we cannot fully
explore suburban development, reverse commuting, and suburb-to-suburb
commuting. The county level analysis in this report does show major
increases in commuting from the central county to suburban counties,
and major increases in suburban county to suburban county. Because
the objective of this report was to update the county level commuting
flows presented in the earlier Trends report, movements of workers
within counties, or along specific high density corridors within
counties are beyond the scope of this analysis.5 Also, for each
metropolitan area, its central county and suburban counties often make
up much different proportions of total land area. All data should be
evaluated in this light.
The 1990 census data reported in STF 3A are based on a sample and
are therefore subject to both sampling and nonsampling errors.
Sampling error in data arises from the selection of persons and
housing units to be included in the sample. Nonsampling error affects
both sample and 100-percent data, and is introduced as a result of
errors that may occur during the collection and processing phases of
the census.
Each housing unit in the country received one of two versions of
the census questionnaire: 1) a short-form that contained certain basic
demographic and housing questions (100-percent questions), and 2) a
long-form that contained the 100-percent items and a number of
additional questions. For the long-form, the primary sampling unit
for the 1990 census was the housing unit, including all occupants.
Three sampling rates were employed. Rural areas (fewer than 2,500
persons) were sampled at a rate of 1-in-2. Urban areas were sampled
at a rate of 1-in-8. All other areas were sampled at a rate of 1-in-
6. When all sampling rates were taken into account across the U.S.,
approximately 1-in-6 housing units were included in the 1990 census
sample.
Geography Considerations
Definition of Metropolitan Area. The general concept of a
metropolitan area (MA) is a large population nucleus surrounded by
adjacent communities that have a high degree of economic and social
-------------------
5For more detailed information at the local level, readers can
consult the Census Transportation Planning Packages (CTPP) published
by the Census Bureau, or other STF data series.
1-5
integration with that nucleus. Some MA's are defined around two or
more nuclei. Each MA must contain either a place with at least 50,000
inhabitants or an urbanized area and a total population of at least
100,000 (75,000 in New England). An MA may also include one or more
outlying counties that have close economic and social relationships
with the central county. An outlying county must have a specified
level of commuting to the central counties and also must meet certain
standards regarding metropolitan character, such as population
density, urban population, and population growth. In New England,
MA's are composed of cities and towns rather than whole counties.
If an area has more than one million inhabitants and meets certain
other requirements specified in the Metropolitan Area standards
published in the Federal Register,6 it is termed a Consolidated
Metropolitan Statistical Area (CMSA), consisting of two or more major
components recognized as Primary Metropolitan Statistical Areas
(PMSA's). Metropolitan Statistical Areas (MSA's) are relatively
freestanding MA's and are not closely associated with other MA's.
These areas typically are surrounded by nonmetropolitan areas. The
OMB defines MA's in terms of entire counties, except in the six New
England states where they are defined in terms of cities and towns.
The set of areas known as MSA's, PMSA's, and CMSA's are collectively
designated MA's. In this report, there are 19 CMSA's and 20 MSA's.7
Revisions to Geographic Boundaries. The MSA/CMSA boundaries in the
Trends report were based on the 1974 Census boundary definitions. The
1990 Decennial Census uses the updated 1983 Census boundary
definitions. A DOT Working Group on Journey to Work decided to adopt
the new boundary definitions and work backward to revise the 1980 data
to conform with the new definitions. Readers should note that in all
the tables and figures presented in this report, the data for New York
City do not include the New England portion of the CMSA (i.e.,
Fairfield County, Connecticut). Table 1-2 below indicates the effect
of geography revisions on specific metropolitan areas. The boundaries
of ten metropolitan areas remained unchanged. In twenty-three
metropolitan areas the geography increased. Six areas actually
decreased in size as a result of the revision process.
For 1980 data, the geographic boundaries used in the earlier Trends
report were adjusted to updates based on the new geography. Counties
that were either added or removed from the thirty-nine MSA's/CMSA's
were identified. Due to the way in which data were collected, it was
not possible to adjust data from 1960 or 1970 using the new
boundaries.8 The DOT Working Group preferred to continue using the
central county as a unit of analysis. Analysis based on the unit of
central city was considered, but ultimately considered unsatisfactory
for this report.9 The Working Group also decided to limit the scope
to metropolitan areas with over one million inhabitants.
-------------------
6FR (12154-12160), March 30, 1990.
7Two terms that were used in the 1980 Census are no longer being
used. These are the Standard Metropolitan Statistical Area (SMSA),
and the Standard Consolidated Statistical Area (SCSA).
8Data for many counties that had been added to the definitions of
metropolitan areas over the years were not covered in the necessary
detail previous to their inclusion in the new boundaries.
9In each MSA and CMSA, the largest place and, in some cases,
additional places are designated as central cities. The largest
central city, and in some cases, up to two additional central cities
are included in the title of the MA; there are also central cities
that are not included in an MA title. An MA central city does not
include any part of that city that extends outside the MA boundary.
1-6
Two sets of trends are presented in the tables in the following
chapters: 1) the 1974 OMB geographic definitions are used to show data
comparisons for 1960, 1970, and 1980; and 2) the 1983 OMB definitions
are used to compare data for 1980 and 1990. Thus, there will be two
observations for 1980 data; existing 1980 data are revised using the
1983 definitions, but not 1970 or 1960. Figure 1-1 illustrates how
the change in geography affects the 1980 count of suburban population
in the thirty-nine metropolitan areas. In presenting the tables,
tables using the 1983 OMB definition for 1980 data have an "A" in the
table number suffix. Tables using the 1974 OMB definition for 1980
data do not have an "A" in the table number suffix.
New England. As in the Trends report, the New England portion will
continue to be excluded from the New York CMSA. The Boston and
Providence metropolitan areas were excluded from the 1960 and 1970
data sets. These exclusions will continue, except for most 1980 and
1990 tabulations. Hartford is new to the list, and only 1980 and 1990
data will be presented, due to the grouping of data by cities and
towns rather than counties. The NECMA10 definition is employed to
include the New England areas in particular analyses.
Data Definitions
Urban and Rural. The Census Bureau defines "urban" for the 1990
census as comprising all territory, population, and housing units in
urbanized areas and in places of 2,500 or more persons outside
urbanized areas. More specifically, "urban" consists of territory,
persons, and housing units in: 1) Places of 2,500 or more persons
incorporated as cities, villages, boroughs (except in New York), and
towns (except in the six New England states, New York, and Wisconsin),
but excluding the rural portions of "extended cities"; 2) Census
designated places of 2,500 or persons; 3) Other territory,
incorporated or unincorporated, included in urbanized areas.
Territory, population, and housing units not classified as urban
constitute "rural". The urban and rural classification cuts across the
other hierarchies; for example, there is generally both urban and
rural territory within both metropolitan and nonmetropolitan areas.
To improve its measure of urban territory, population, and housing
units, the Census Bureau adopted the concept of the urbanized area and
delineated boundaries for unincorporated places (now, census
designated places) for the 1950 census. This "urban" definition has
remained basically unchanged since then.
Household. A household includes all the persons who occupy a
housing unit. A housing unit is a house, an apartment, a mobile home,
a group of rooms, or a single room that is occupied (or if vacant, is
intended for occupancy) as separate living quarters. Separate living
quarters are those in which the occupants live and eat separately from
any other persons in the building and which have direct access from
the outside of the building or through a common hall. The occupants
may be a single family, one person living alone, two or more families
living together, or any other group of related or unrelated persons
who share living arrangements. In 100-percent tabulations, the count
of households or householders always equals the count of occupied
housing units. In sample tabulations, the numbers may differ as a
result of the weighting process.
-------------------
10Readers should take note that in computing some of the data series
for New England metropolitan areas (Boston, Providence, and
Hartford), the New England County Metropolitan Area (NECMA) definition
is used to delineate county boundaries. This was necessary to
maintain consistency with other parts of the U.S., since in New
England metropolitan areas are defined by cities and towns, and hence
leading to only partial county coverage (rather than the complete
county coverage that NECMA's provide).
1-7
Table 1-2. Effect of 1983 OMB Revisions on Geographies of 1990
Metropolitan Areas With Over One Million Inhabitants
Geography Geography Geography New Areas
Unchanged Increased Decreased in 1990
Los Angeles New York Dallas Norfolk
Houston Chicago Atlanta Charlotte
Miami San Francisco Denver Hartford
Cleveland Philadelphia Cincinnati Orlando
Seattle Detroit Indianapolis Salt Lake City
San Diego Boston Providence Rochester
Phoenix Washington
Milwaukee Minneapolis
San Antonio St. Louis
Buffalo Baltimore
Pittsburgh
Tampa
Kansas City
Sacramento
Portland
Columbus
New Orleans
Figure 1.1 Effect of Geographic Revisions on Suburban Population,
Thirty-Nine Metropolitan Areas, 1960-1990.
Click HERE for graphic.
1-8
Persons per household is a measure obtained by dividing the number
of persons in households by the number of households. In cases where
persons in households are cross-classified by race or Hispanic origin,
the race or Hispanic origin of the householder is used rather than the
race or Hispanic origin of each individual.
Income of Households and Median Income. Includes the income of the
householder and all other persons 15 years old and over in the
household, whether related to the householder or not.
Because many households consist of only one person, average
household income is usually less than family income.
The median divides the income distribution into two equal parts,
one having incomes above the median and the other having incomes below
the median. For households and families, the median income is based
on the distribution of the total number of units including those with
no income. The median for persons is based on persons with income.
The median income values for all households, families, and persons are
computed on the basis of more detailed income intervals than shown in
most tabulations. Median household or family income figures of
$50,000 or less are calculated using linear interpolation. For
persons, corresponding median values of $40,000 or less are also
computed using linear interpolation.
Vehicles Available. The data on vehicles available were obtained
from questionnaire item H13, which was asked at occupied housing units
on a sample basis. These data show the number of households with a
specified number of passenger cars, vans, and pickup or panel trucks
of one-ton capacity or less kept at home and available for the use of
household members. Vehicles rented or leased for one month or more,
company vehicles, and police and government vehicles are included if
kept at home and used for non-business purposes. Dismantled or
immobile vehicles are excluded. Vehicles kept at home but used only
for business purposes also are excluded. Vehicles per household is
computed by dividing aggregate vehicles available by the number of
occupied housing units.
Limitations. 1980 census evaluations showed that the number of
automobiles were slightly overreported, the number of vans and
trucks slightly underreported. The statistics do not measure the
number of vehicles privately owned or the number of households
owning vehicles. Data on automobiles available were collected from
1960 to 1980. In 1980, a separate question also was asked on the
number of trucks and vans. The data on automobiles and trucks and
vans were presented separately and also as a combined vehicles
available tabulation. The 1990 data are comparable to the 1980
vehicles available tabulations.
Employment Status. The data on employment status were derived from
answers to questionnaire items 21, 25, and 26, which were asked of a
sample of persons. The series of questions on employment status was
asked of all persons 15 years old and over and was designed to
identify, in this sequence: (1) persons who worked at any time during
the reference week; (2) persons who did not work during the reference
week but who had jobs or businesses from which they were temporarily
absent (excluding layoff); (3) persons on layoff; and (4) persons who
did not work during the reference week, but who were looking for work
the last four weeks and were available for work during the reference
week.
The employment status data shown in this and other 1990 census
tabulations relate to persons 16 years old and over. Some tabulations
showing employment status, however, include persons 15 years old. By
definition, these persons are classified as "Not in Labor Force." In
the 1940, 1950, and 1960 censuses, employment status data were
presented for persons 14 years old and over. The change in the
universe was made in 1970 to agree with the official measurement of
the labor force as revised in January 1967
1-9
by the U.S. Department of Labor. The 1970 census was the last to show
employment data for persons 14 and 15 years old.
Employed persons are defined as all civilians 16 years old and over
who were either (1) "at work" - those who did any work at all during
the reference week as paid employees, worked in their own business or
profession, worked on their own farm 15 hours or more as unpaid
workers on a family farm or in a family business; or (2) were "with a
job but not at work" - those who did not work during the reference
week but had jobs or businesses from which they were temporarily
absent due to illness, bad weather, industrial dispute, vacation, or
other personal reasons. Excluded from the employed are persons whose
only activity consisted of work around the house or unpaid volunteer
work for religious, charitable, and similar organizations; also
excluded are persons on active duty in the United States Armed Forces.
Limitations. The census may understate the number of employed
persons because persons who have irregular, casual, or unstructured
jobs sometimes report themselves as not working. The number of
employed persons "at work" is probably overstated in the census
(and conversely, the number of employed "with a job, but not at
work" is understated) because some persons on vacation or sick
leave erroneously reported themselves as working. This problem has
no effect on the total number of employed persons. Since persons
can change their employment status from one week to another, the
lack of a uniform reference week may mean that the employment data
do not reflect the reality of the unemployment situation of any
given week.
Place of Work. The data on place of work were derived from answers
to questionnaire item 22, which was asked of persons who indicated in
question 21 that they worked at some time during the reference week.
Data were tabulated for workers 16 years and over; that is, members of
the Armed Forces and civilians who were at work during the reference
week. Data on place of work refer to the geographic location at which
workers carried out their occupational activities during the reference
week. The exact address (number and street) of the place of work was
asked, as well as the place (city or town, or post office); whether or
not the place of work was inside or outside the limits of that city or
town; and the county, State, and Zip code. If the person's employer
operated in more than one location, the exact address of the location
or branch where the respondent worked was requested. When the number
and street name were unknown, a description of the location, such as
the building name or nearest street or intersection, was entered.
Persons who worked at more than one location during the reference
week were asked to report the one at which they worked the greatest
number of hours. Persons who regularly worked in several locations
each day during the reference week were requested to give the address
at which they began work each day. For cases in which daily work did
not begin at a central place each day, the person was asked to provide
as much information as possible to describe the area in which he or
she worked most during the reference week.
In some tabulations, place-of-work locations may be defined as "in
area of residence" and "outside area of residence." The area of
residence may vary from table to table or even within a table. For
example, in a table that provides data for counties, "in area of
residence" refers to persons who worked in the same county in which
they lived, while "outside area of residence" refers to persons whose
workplace is different from the one in which they lived. Similarly,
in a table that provides data for several types of areas, such as the
State and its individual metropolitan areas, counties, and places, the
place-of-work data will be variable and is determined by the
geographic level (State, metropolitan area, county, or place) shown in
each section of the tabulation.
1-10
In tabulations that present data for an MSA/PMSA, place-of-work
locations are specified to show the main destinations of workers
living in the MSA/PMSA. All place-of-work locations are identified
with respect to the boundaries of the MSA/PMSA as "inside MSA/PMSA" or
"outside MSA/PMSA." Locations within the MSA/PMSA are further divided
into each central city, and each county or county balance. Selected
large incorporated places also may be specified as places to work.
Within New England MSA/PMSA's, the places of work presented
generally are cities and towns. Locations outside MSA/PMSA's are
specified if they are significant commuting destinations for residents
of major MSA/PMSA's and their central cities, component counties,
large incorporated places, or counties, cities, or other geographic
area outside any metropolitan area. In tabulations for MSA/PMSA's in
New England and certain other metropolitan areas, some place-of-work
locations are identified as "areas" (e.g., Area 1, Area 5, Area 12,
etc.). Such areas consist of groups of towns, cities, or counties
that have been identified as unique place-of-work destinations. When
an adjoining MSA/PMSA or MSA/PMSA remainder is specified as a place-
of-work location, its components are not defined. However, the
components are presented in the 1990 CP-1, General Population
Characteristics for Metropolitan Areas and the 1990 CH-1, General
Housing Characteristics for Metropolitan Areas reports. In
tabulations that present data for census tracts outside metropolitan
areas, place-of-work locations are defined as "in county of residence"
and "outside county of residence."
Place-of-work data are given for selected minor civil divisions
(generally, cities, towns, and townships) in the nine Northeastern
States, based on the responses to the place-of-work question. Many
towns and townships are regarded locally as the equivalent of a place
and therefore, were reported a locality or incorporated place that
formed a part of a township or town. The accuracy of the place-of-
work data for minor civil divisions is greatest for the New England
States. However, the data for some New England towns, for towns in
New York, and for townships in New Jersey and Pennsylvania may be
affected by coding problems that resulted from the unfamiliarity of
the respondent with the minor civil division in which the workplace
was located or when a township and a city or borough of the same or
similar name are located close together.
The wording of the question on place of work was substantially the
same in the 1990 census as it was in 1980. However, data on place of
work from the 1990 census are based on the full census sample, while
data from the 1980 census were based on only about one-half of the
full sample. For the 1980 census, nonresponse or incomplete responses
to the place-of-work question were not allocated, resulting in the use
of "not reported" categories in the 1980 publications. However, for
the 1990 census, when place of work was not reported or the response
was incomplete, a work location was allocated to the person based on
their means of transportation to work, travel time to work, industry,
and location of residence and workplace of others. The 1990
publications, therefore, do not contain a "not reported" category for
the place-of-work data.
Comparisons between 1980 and 1990 census data on the gross number
of workers in particular commuting flows, or the total number of
persons working in an area, should be made with extreme caution. Any
apparent increase in the magnitude of the gross numbers may be due
solely to the fact that for 1990 the "not reported" cases have been
distributed among specific place-of-work destinations, instead of
tallied in a separate category as in 1980. In this report, the
numbers in tables have been distributed.
Limitations. The data on place of work relate to a reference week;
that is, the calendar week preceding the date on which the
respondents completed their questionnaires or were interviewed by
enumerators. This week is not the same for all respondents because
the enumeration was not completed in 1 week. However, for the
majority of persons, the reference week for the 1990
1-11
census is the last week in March 1990. The lack of a uniform
reference week means that the place-of-work data reported in the
census will not exactly match the distribution of workplace
locations observed or measured during an actual workweek. The
place-of-work data are estimates of persons 16 years old and over
who were both employed and at work during the reference week
(including persons in the Armed Forces). Therefore, the data on
place of work understate the total number of jobs or total
employment in a geographical area during the reference week. It
also should be noted that persons who had irregular, casual, or
unstructured jobs during the reference week may have erroneously
reported themselves as not working.
The address where the individual worked most often during the
reference week was recorded on the census questionnaire. If a
worker held two jobs, only data about the primary job (the one
worked the greatest number of hours during the preceding week) was
requested. Persons who regularly worked in several locations
during the reference week were requested to give the address at
which they began each day. For cases in which daily work was not
begun at a central place each day, the person was asked to provide
as much information as possible to describe the area in which he or
she worked most during the reference week.
Means of Transportation. The data on means of transportation to
work were derived from answers to questionnaire item 23a, which was
asked of persons who indicated in question 21 that they worked at some
time during the reference week. Means of Transportation to work
refers to the principal mode of travel or type of conveyance that the
person usually used to get from home to work during the reference
week.
Persons who used different means of transportation on different
days of the week were asked to specify the one they used most often.
Persons who used more than one means of transportation to get to work
each day were asked to report the one used for the longest distance
during the work trip. The category, "Public transportation," includes
workers who used a bus or trolley bus, streetcar or trolley car,
subway or elevated rail, railroad, ferryboat, or taxicab even if each
mode is not identified separately within the data distribution. The
category, "Other means," may vary from table to table, depending on
the amount of detail shown in a particular distribution.
The means of transportation data for some areas may show workers
using modes of public transportation that are not available in those
areas (e.g., subway or elevated riders in a metropolitan area where
there actually is no subway or elevated service). This result is
largely due to persons who worked during the reference week at a
location that was different from their usual place of work (such as
persons away from home on business in an area where subway service was
available) and persons who used more than one means of transportation
each day but whose principal means was unavailable where they lived
(for example, residents of nonmetropolitan areas who drove to the
fringe of an metropolitan area and took the commuter railroad most of
the distance to work).
Private Vehicle Occupancy. The data on private vehicle occupancy
were derived from answers to questionnaire item 23b. This question
was asked of persons who indicated in question 21 that they worked at
some time during the reference week and who reported in question 23a
that their means of transportation to work was "car, truck, or van."
Private vehicle occupancy refers to the number of persons who usually
rode to work in the vehicle during the reference week. Other
transportation discussions on vehicle occupancy may use occupancy that
is weighted by trip length.
The category, "Drove alone," includes persons who usually drove
alone to work as well as persons who were driven to work by someone
who then drove back home or to a nonwork destination. The
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category, "Carpooled," includes workers who reported that two or more
persons usually rode to work in the vehicle during the reference week.
The measure persons per car, truck, or van is obtained by dividing
the number of persons who reported using a car, truck, or van to get
to work by the number of such vehicles that they used. The number of
vehicles used is derived by counting each person who drove alone as
one vehicle, each person who reported being in a two-person carpool as
one-half vehicle, each person who reported being in a three-person
carpool as one third vehicle, and so on, and then summing all the
vehicles.
Time Leaving Home to Go to Work. The data on time leaving home to
go to work were derived from answers to questionnaire item 24a. This
question was asked of persons who indicated in question 21 that they
worked at some time during the reference week and who reported in
question 23a that they worked outside their home. The departure time
refers to the time of day that the person usually left home to go to
work during the reference week.
Travel Time to Work. The data on travel time to work were derived
from answers to questionnaire item 24b. This question was asked of
persons who indicated in question 21 that they worked at some time
during the reference week and who reported in question 23a that they
worked outside their home. Travel time to work refers to the total
number of minutes that it usually took the person to get from home to
work during the reference week. The elapsed time includes time spent
waiting for public transportation, picking up passengers in carpools,
and time spent in other activities related to getting to work.
1-13
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1-14
Chapter 2
NATIONAL SUMMARY
Commuting Indicators
Thirty Year Trends. Commuting behavior by U.S. workers can be
viewed as an outcome of demographic characteristics, the supply and
location of jobs, the costs and availability of various commuting
options, and perceived travel time. Over the 1960-1990 period there
were a number of factors that influenced commuting behavior in both
quantity and magnitude. Table 2-1 highlights national data from the
1960, 1970, 1980 and 1990 decennial censuses and their journey-to-work
components.1 This table compares broad measures and characteristics
of the population, workers, commuting activities, and mode of travel.
Table 2-2 displays similar information for the 1960-1990 period, but
focuses on comparisons between totals for the U.S. and large
metropolitan areas with over one million inhabitants.
As the two tables show, over the period 1960-1990 the U.S. general
population increased from 179 million to almost 249 million.
Meanwhile, the number of workers rose from about 65 million to 115
million, or almost twice the growth rate of the population. There was
also a sharp drop in household size. In 1960, the typical household
had 3.33 persons, but by 1990 household size had diminished to 2.63
persons - a decrease of 21%. The totals for large metropolitan areas
show results comparable to the U.S. figures. Table 2-2 shows greater
growth for population and workers in metropolitan areas, but much of
the difference is caused by the addition of several new metropolitan
areas over the period. The percentage of workers commuting by
privately owned vehicles (POV) is higher outside of the metropolitan
areas. Otherwise, the ratios show little difference between the U.S.
and metropolitan areas.
Throughout the period, the percent of workers who worked outside
their county of residence grew by over 200%, suggesting the
progressive suburbanization of places of work. With greater economic
activity came a higher standard of living for many households, and
with it the ability to buy more automobiles. The Interstate Highway
System was virtually completed during these years. The total number
of vehicles in households increased over threefold. The average
household in 1960 had only 1.03 vehicles, but by 1990 it had 1.66
vehicles. The fastest rising category during the period was
households with three or more vehicles. By 1990, nearly 16 million
U.S. households had three or more vehicles, or about 17% of all U.S.
households.
During the 1960-1990 period, the baby-boomers grew from a
population of school-aged children into working adults in their
thirties and forties. The rapid growth in U.S. workers was driven in
large measure by these baby-boomers entering the labor force. Also of
note was the increase in workers per household, representing an
increase in women in the labor force. In 1960, females made up 33.6%
of all workers in large metropolitan area, but by 1990 females formed
45.6% of total workers. Another important change was a declining
birth rate. In 1960, the U.S. had a birth rate per of 23.8 per
thousand, but by 1990, the birth rate had dropped to 16.7.2
-------------------
1For the sake of clarity, and in order to illuminate these broader
trends, the subject of geographic redefinition of metropolitan areas
is left for later chapters. While such changes are not ordinarily
evident in state and national level tabulations, readers for now
should keep in mind that issues of geography and measurement are
closely linked.
2The birth rate appears to have bottomed out in 1986 at 15.5.
2-1
153-916 0 - 94 - 2
Table 2.1. Journey-to-Work Comparisons, National Totals, 1960-1990
Click HERE for graphic.
2-2
Table 2.2. National Trends 1960-1990 Factors, U.S. Totals Compared
to Metropolitan Areas With Over One Million Inhabitants.
U.S. Metropolitan
Factor Totals Area Totals3
Population
1960. . . . . . . . . . . 179,323,175 . . . . . 77,175,875
1990. . . . . . . . . . . 248,709,873 . . . . . 123,814,261
Percent Change. . . . . . 38.69%. . . . . . . . 60.43%
Workers
1960. . . . . . . . . . . 64,655,805. . . . . . 29,033,438
1990. . . . . . . . . . . 115,070,274 . . . . . 59,704,401
Percent Change. . . . . . 77.97%. . . . . . . . 105.64%
Male/Female Worker Ratio
1960. . . . . . . . . . . 67.7%/32.3% . . . . . 66.4%/33.6%
1990. . . . . . . . . . . 54.7%/45.3% . . . . . 54.4%/45.6%
Persons/Household
1960. . . . . . . . . . . 3.33. . . . . . . . . 3.24
1990. . . . . . . . . . . 2.63. . . . . . . . . 2.65
Percent Change. . . . . . 21.02 . . . . . . . . -21.40%
Workers/Household
1960. . . . . . . . . . . 1.22. . . . . . . . . 1.24
1990. . . . . . . . . . . 1.25. . . . . . . . . 1.31
Percent Change. . . . . . 2.58% . . . . . . . . 5.65%
Vehicles/Household
1960. . . . . . . . . . . 1.03. . . . . . . . . 1.00
1990. . . . . . . . . . . 1.66. . . . . . . . . 1.59
Percent Change. . . . . . 60.37%. . . . . . . . 59.00%
Vehicles/Person
1960. . . . . . . . . . . 0.31. . . . . . . . . 0.31
1990. . . . . . . . . . . 0.61. . . . . . . . . 0.58
Percent Change. . . . . . 100.61% . . . . . . . 87.10%
% Workers Traveling by POV
1960. . . . . . . . . . . 66.49%. . . . . . . . 61.03%
1990. . . . . . . . . . . 88.02%. . . . . . . . 83.44%
-------------------
3The list of metropolitan areas over one million has increased over
the thirty year period from thirty-four to thirty-nine areas. In
addition, there have been a few areas that lost population and hence
no longer on the list. These facts should be considered when
interpreting this table.
2-3
Over the past thirty years, many areas of the country have been
making the transition from a manufacturing based labor force to
service sector jobs. Service sector employment in the U.S. has
displaced the predominant role held by manufacturing for many decades.
The concentrated centers of industrial activity that characterized
manufacturing employment in the early years of the 1960-1990 period
are now being replaced by the service sector and high technology jobs
of the 1990's.
The geographies of metropolitan areas have been altered to
accommodate the increasingly decentralized nature of workers' places
of work and residences. Metropolitan areas on the East and West
coasts, in particular, have grown geographically closer, as
populations and jobs alike have spread out from the urban cores. Some
neighboring metropolitan areas no longer have rural or semi-rural
areas separating them.
During the thirty years, American workers continued to convey their
established preference for private automobile travel. Noteworthy is
the large amount of highway construction that took place during the
early part of the period, providing the capacity for more vehicles.
Compared to 1960 and 1970 data on surfaced roadways, however, current
data reflects a slowing of construction in recent years.4 Sales of
new passenger cars totaled 6.7 million in 1960, and about 6 million in
1990, despite several years of more robust sales in the 1970's and
early 1980's. People are keeping their cars for a longer time; the
average age of a household vehicle grew from 5.1 years in 1969 to 7.7
years in 1990.5
Looking ahead, new technologies in telecommunications and
transportation promise to lessen the differences between traditional
central business districts and dispersed employment areas of the
suburbs. Service sector employment is transforming how jobs are
performed, the time it takes to accomplish them, where they are
located, and the mode of travel used to reach them. For example, the
technology to permit people to work at home through computer networks
is changing rapidly. This technology may have significant impacts on
journey-to-work decisions, but we do not as yet know the scope or the
timing of these impacts.
Ten Year Trends. The trends between 1980 and 1990 include smaller
but increasing numbers of households, population dispersion,
increasing urbanization, a large growth in workers particularly in the
service sector, and increasing female labor force participation.
Housing costs increased in the East and West coasts during the 1980's.
Housing costs are a major determinant of residence location, and could
have indirectly affected journey-to-work data in those locales. Table
2-3 below compares ten year trends for metropolitan areas with U.S.
totals for some common commuting factors. In the 1980's population in
the U.S. grew by 9.78%, while in large metropolitan areas it grew by
11.81%. The number of workers rose at over twice the rate of
population. Both workers per household and vehicles per household
were slightly higher outside metropolitan areas.
-------------------
4Data from the FHWA's Highway Statistics shows the following:
U.S. Road and Street 1960 1970 1980 1990
Mileage, Surfaced (millions) 2.56 2.95 3.36 3.52
5Source: Hu, P.S., and Young, J. "Summary of Travel Trends, 1990
Nationwide Personal Transportation Survey" (U.S. DOT/FHWA, March,
1992).
2-4
Table 2-3. Ten Year Trends in Journey-to-Work Factors, U.S. Totals
Compared to Metropolitan Areas With Over One Million Inhabitants
(based on 1983 geography)
U.S. Metropolitan
Factor Totals Area Totals
Population
1980 . . . . . . . . . . . . .226,545,805. . . . . . . 110,732,144
1990 . . . . . . . . . . . . .248,709,873. . . . . . . 123,814,261
Percent Change . . . . . . . . . 9.78%. . . . . . . 11.81%
Workers
1980 . . . . . . . . . . . . .96,617,296 . . . . . . . 46,444,001
1990 . . . . . . . . . . . . .115,070,274. . . . . . . 59,704,401
Percent Change . . . . . . . . . 19.10%. . . . . . . 21.56%
Workers/Household
1980 . . . . . . . . . . . . . 1.20 . . . . . . . 1.18
1990 . . . . . . . . . . . . . 1.25 . . . . . . . 1.24
Vehicles/Household
1980 . . . . . . . . . . . . . 1.61 . . . . . . . 1.52
1990 . . . . . . . . . . . . . 1.66 . . . . . . . 1.59
Table 2-4 presents a detailed profile of national and metropolitan
data for 1990 only. Information is provided on population, workers,
travel time, vehicles, mode, and other related indicators for the U.S.
as a whole, the thirty-nine metropolitan areas over one million, and
the remainder of the nation.6 The thirty-nine metropolitan areas
account for almost 50% of the U.S. population, and almost half the
total household vehicles, but only 5% of the land area. Almost 52% of
all U.S. workers are employed within these metropolitan areas. In
1990, many other comparisons between the U.S. and large metropolitan
areas are similar. Metropolitan area households had an average of
1.31 workers compared to 1.25 workers per household for the entire
U.S. Median household income was just slightly higher in metropolitan
areas. Mean travel time was 22.4 minutes in the U.S., versus 25.2
minutes in the metropolitan areas. Outside the large metropolitan
areas, drive alone commutes were a little higher, and transit usage
was lower. These and other comparisons are listed in Table 2-5 below.
From 1980-1990, both residential and employment densities continued
to increase in suburban counties, maintaining a trend that had become
well-established in the 1970's. Additional changes consisted of
rising vehicle ownership rates, smaller and more fuel efficient cars,
and increases in commuters who drove alone. Later in this report,
these factors are examined in more detail. From 1980-1990, at the
national level, travel times to work did not rise much, although some
differences are found among metropolitan areas. In 1980, the average
reported travel time for the U.S. as a whole was 21.7 minutes, and by
1990 that figure had risen to 22.4 minutes. The relatively small
increase may reflect more driving alone. Also, some commuters shifted
from slower to faster modes of transportation. Table 2-6 provides a
summary of journey-to-work trends from 1980-1990, and lists supporting
facts from the 1990 Census.
-------------------
6This table is duplicated in the Profiles section of this report,
preceding the profiles for each of the thirty-nine metropolitan areas.
2-5
Table 2-4. Journey-to-Work Profile: National Summary Statistics
(1990)
Click HERE for graphic.
2-6
Table 2.5 Selected Demographic and Commuting Comparisons, U.S. and
Large Metropolitan Areas, 1990
U.S. Metropolitan
Factors Totals Area Totals
Population Per Square Mile. . . . 70. . . . . . . . . . 664
Workers Per Square Mile . . . . . 33. . . . . . . . . . 320
Median Household Income . . . . . $30,338 . . . . . . . $31,016
Mean Travel Time (minutes). . . . 22.4. . . . . . . . . 25.2
Total Vehicles (millions) . . . . 152.4 . . . . . . . . 72.5
% Workers Driving Alone . . . . . 73.2. . . . . . . . . 70.8
% Workers Carpooling. . . . . . . 13.4. . . . . . . . . 12.7
% Workers Using Transit . . . . . 5.3 . . . . . . . . . 9.0
In analyzing large data sets, it is often helpful to quickly scan
the range of statistics, such as those presented in Tables 2-7 and 2-
8. These tables compare selected maximum and minimum data values for
states and metropolitan areas, respectively. Metropolitan area level
data frequently parallel the state level data in terms of maximum and
minimum values. This suggests that similar patterns are occurring at
micro and macro levels within a state, or that the effects of a large
metropolitan area dominate state data totals. Work trips in the state
of New York averaged 27.8 minutes, while trips in North Dakota
required an average of only 11.9 minutes. For the thirty-nine
metropolitan areas, New York state had both the metropolitan area with
the highest and the area with the lowest mean travel times in 1990.
The highest mean travel time was 31.7 minutes in New York City, the
lowest was in Buffalo at 19.4 minutes.
Household Formations. The pattern of more but smaller households
seems firmly in place and may hold significance both for journey-to-
work decisions and transportation planning. From 1960-1990, the
number of U.S. households rose from 53 million in 1960 to 92 million
in 1990, almost 75% increase. The increase in the number of
households is also reflected in declining household size. In 1980,
the average household had 2.75 people. This dropped 4.4% in 1990 to
2.63 people per household.
Urban Populations.7 From 1960-1990, the urban population in the
country advanced by nearly 50%, compared to a corresponding rural
population increase of 14%. By 1990, three-fourths of all persons
lived within areas defined as urban. For the entire United States,
urban population rose in the 1980's by almost 12%. Individual states
varied widely; Nevada's urban population rose over 55%, and both
Alaska and Arizona rose over 40%. On the other hand, West Virginia
had a loss of 8.1% in urban residents, and Louisiana and Iowa had
small losses as well. The data indicate that migration to high growth
states is concentrated in their urban areas.
Growth in the Number of Workers. From 1960 to 1990, the total number
of workers in the U.S. grew in absolute terms by 78%. The U.S. had
over 115 million workers in 1990, about 46.3% of the total population.
In 1960, only 36.1% of the population were workers. Nationwide, the
number of workers sixteen years old and older increased sharply in the
1980-1990 period, both in absolute figures
-------------------
7The Census Bureau defines "urban" for the 1990 census as comprising
all territory, population, and housing units in urbanized areas and in
places of 2,500 or more persons outside urbanized areas. All other
area is classified as rural. Also, the Census Bureau defines an
Urbanized Area (UA) as one or more places (central place) and the
adjacent densely settled surrounding territory (urban fringe) that
together have a minimum of 50,000 persons.
2-7
Table 2-6. Indicators, Trends, and Factsheet for Journey-to-Work
Patterns, 1980-1990
Click HERE for graphic.
2-8
Table 2-7. Journey to Work, 1990, Maximums and Minimums by State
Choice of Mode to Work in 1990
Mode Choice State Maximum State Minimum
Drive Alone . . Michigan. . . . . . . 81.5% . . New York. . . 54.3%
Carpool . . . . Hawaii. . . . . . . . 20.5% . . South Dakota. 10.1%
Public Transit. New York. . . . . . . 24.8% . . South Dakota. 0.3%
Walk. . . . . . District of Columbia. 11.8% . . Alabama . . . 1.9%
Work at Home. . South Dakota. . . . . 9.5% . . Alabama . . . 1.8%
Other . . . . . Alaska. . . . . . . . 4.5% . . Minnesota . . 0.5%
Household Vehicle Ownership in 1990
Households With State Maximum State Minimum
Zero Vehicles . . . . . .New York . . . 30.0% . . .Idaho. . . 4.6%
One Vehicle . . . . . . .Florida. . . . 41.0% . . .Idaho. . . 28.1%
Two Vehicles. . . . . . .New Hampshire. 44.2% . . .New York . 26.5%
Three or More Vehicles. .Wyoming. . . . 27.4% . . .New York . 11.1%
Commuting Indicators From the 1990 Census
Indicator State Maximum State Minimum
Mean Travel Time
To Work (minutes) . . . .New York . . 27.80 . .North Dakota . 11.90
Persons Per Household . .Utah . . . . 3.15 . .Florida. . . . 2.46
Workers Per Household . .Hawaii . . . 1.59 . .West Virginia. 0.97
Workers as Percent of
Population. . . . . . . .Maryland . . 51.90%. .West Virginia. 34.30%
Vehicles Per Household. .Wyoming. . . 1.98 . .New York . . . 1.22
Vehicles Per Worker . . .Montana. . . 1.66 . .New York . . . 0.98
Workers Per Vehicle . . .New York . . 1.02 . .Montana. . . . 0.60
Median Household
Income. . . . . . . . . .Connecticut. $41,721 .Mississippi. . $20,136
2-9
Table 2-8. Journey to Work, 1990, Maximums and Minimums by
Metropolitan Area
Click HERE for graphic.
2-10
and as a percentage of the resident population. Total workers rose by
over 19%, more than twice the growth of the total resident population.
Nevada led all states with a 52% increase in workers, followed closely
by Alaska and Florida.
A significant proportion of the increase in workers may be
attributable to the increase of women in the workforce (Table 2-9).
Recent data8 indicate a compound annual growth rate of 2.9% for
female workers compared to 1.6% for male workers. The labor force
participation rates by sex over the 1960-1990 period reveal the
changing mix.
Table 2-9. Labor Force Participation Rates by Sex, Percentages,
1960-1990
Sex 1960 1970 1980 1990
Male 83.3% 79.7% 77.4% 76.1%
Female 37.7 43.3 51.5 57.5
Workers per Household. The average number of workers per household
remained nearly the same during 1960 to 1980. From 1980-1990, workers
per household rose from 1.20 to 1.25, an increase of 4%. This
apparently static trend must be evaluated in combination with dramatic
declines in household size. In 1960, there were 1.22 workers and an
average household size of 3.33. In 1990, there was an average of 1.25
workers, and average household size of 2.63.
During the past decade, a 9% increase in workers per household was
recorded in California, while New York and New Jersey each had gains
of about 8%. Workers per household fell in Texas, Louisiana, and
Wyoming, probably due to weakness in the energy industry.
California was the only state with an increase in persons per
household. This ratio rose by over 4% from 1980-1990. Possible
explanations include: a large immigrant population; above average
birth rates; and high housing costs, forcing more people to share
living quarters. Taking 1985 as the midpoint year of the 1980's,
California had several metropolitan areas among the leaders in median
sales prices of existing single family homes. Also in 1985,
California's birth rate per thousand was 17.9, compared to a national
average of 15.8.9
Density Indicators. Figure 2-1 illustrates several data series
(persons, vehicles, workers, households) expressed in terms of square
miles in the metropolitan area. Population density is always the
highest of these measures, and produces similar increases in the other
data. The numbers show fairly uniform correlation across the thirty-
nine metropolitan areas, only the older industrialized areas like New
York, Chicago, Boston, and Philadelphia display much higher densities.
In these cities, most of the indicators lie well above 500 units per
square mile.
-------------------
8Employment and Earnings, U.S. Department of Labor, Bureau of Labor
Statistics, p. 173, January 1993.
9Source: Statistical Abstract of the United States.
2-11
Figure 2-1. Selected Density Indicators, 1990 - 39 Metropolitan Areas
Click HERE for graphic.
2-12
Care must be exercised in interpreting these densities.
Metropolitan area boundaries are periodically redefined to add new
counties, often with lower densities. The net effect is that
densities are often diluted, although the densities in the previously
defined metropolitan area may have increased.
The distribution of worker densities closely matches changes in
population density. Some exceptions should be noted, since local
demographics can create atypical differences. Sunbelt locations, for
example, generally have a higher incidence of retirees resulting in
lower work densities.
Choice of Mode to Work
Driving alone to work has consistently increased at each census
point from 1960 to 1990 while carpooling has consistently decreased.
Figure 2-2 compares the thirty-nine metropolitan areas with nationwide
totals of mode choice for the journey to work. In metropolitan areas,
9% of the journey-to-work trips are made using transit, compared to 5%
nationwide. The 4% difference is largely comprised of commuters who
drive alone (73.4% for U.S. and 71% for metropolitan areas) or travel
in vehicle pools (13.4% for U.S. and 12.7% for metropolitan areas).
The percentage of people who work at home shows little difference
between national and metropolitan area totals.
Driving Alone. Over the thirty year period, the number of people
driving alone to work has increased almost without interruption. The
use of private vehicles for commuting grew by more than 135% over the
period. In 1960, almost forty-three million commuters drove alone and
by 1990, the number had risen to 101 million. As a share of all
commuting trips, the use of private vehicles increased by just under
30% during this period.
One of the major results of the 1990 journey-to-work data, compared
to 1980, is the increase in commuters who drove alone, both in
absolute numbers and as a proportion of all trips. In 1980, 64.4% of
all commuters drove to work alone. By 1990, the drive alone share
increased to 73.2%. The increase in the number of drive alone
commuters in the U.S. was over 35%.
Carpooling. From 1980 to 1990, commuters using carpools declined
substantially, falling 32% nationally. In 1990, the market share for
carpools was 13.3% nationwide. Carpool usage decreased the most in
New England and the North Central states. Hawaii led all states in
carpooling in 1990 with 20.5% of commuting trips. The Washington,
D.C. MSA registered the highest share of carpooling among metropolitan
areas in 1990, with almost 16% of trips by that mode.
Public Transit. Public transit usage declined sharply over the
period, but with temporary upsurges during the years of tight gasoline
supplies in the 1970's. Workers using public transit totaled 7.8
million in 1960 and 5.9 million in 1990. During the 1970's and
1980's, new subway systems were built in the San Francisco Bay area,
Atlanta, and Washington, DC. However, public transit use dropped by
25% altogether in the last thirty years.
In the 1980's, public transit lost market share in the journey to
work, declining from 6.2% in 1980 to 5. 1 % in 1990. Most losses came
at the expense of commuters driving alone. In 1990, the state of New
York ranked first in taking public transit to work, with almost one
quarter of all commuters using that mode. As a mode, public transit
in the U.S. accounted for only about 5% of all journeys to work in
1990. Bus riders were the highest subcomponent of transit users at 3%
of total journeys to work.
2-13
Figure 2.2 Means of Journey to Work, 1990 - National and Metropolitan
Area Totals
Means of Journey to Work, 1990
39 Metropolitan Areas Over One Million
Means of Journey to Work, 1990
National Total
Click HERE for graphic.
2-15
Walking to Work. From 1960-1990, walking to work fell by 30%,
dropping from 6.4 million in 1960 to 4.5 million in 1990. Its share
of all commuting trips also decreased from 10.4% to 3.9%. The number
of commuters who walked to work decreased nationally from 5.4 million
in 1980 to 4.5 million in 1990.
Working at Home. Working at home showed an overall loss of 27% in
the thirty year period, suggesting declines in farming activity. This
category, however, displayed a sharp turnaround during the 1980's in
both absolute numbers and its market share. In 1980, 2.2 million
people worked at home. In 1990, there were 3.4 million in this
category. This change may indicate increases in telecommuting or
other service oriented work at home employment.
Travel Time
Nationwide, travel time to work rose by just 3.2% in the 1980's,
increasing from 21.7 minutes to 22.4 minutes. Inside the thirty-nine
metropolitan areas in 1990, the average travel time was 25.2 minutes.
Ten states reported net decreases in travel time, headed by Wyoming
with a 13.5% drop. The highest percent increases were located in New
Hampshire, Hawaii, and California, all three states having above
average population growth rates in the 1980's. In 1990, New York had
the longest mean travel time with 28.6 minutes, while the fastest was
13 minutes in North Dakota. The modest increases from 1980-1990 may
reflect more driving alone, as commuters shifted from slower to faster
modes of transportation.
Time Leaving Home. A question added in the 1990 Census concerned
departure time for work. There is no pronounced difference in
departure times between the metropolitan areas and the rest of the
nation. The majority of people both inside and outside metropolitan
area chose to leave for work between the hours of 7:00 A.M. and 8:29
A.M. The second most frequent departure interval was between 5:00 A.M.
and 6:59 A.M. Inside the thirty-nine metropolitan areas, 25.49% left
between 5:00 A.M. and 6:59 A.M., while in the remainder of the nation,
26.04% departed between 5:00 A.M. and 6:59 A.M. (Table 2-10).
Table 2-10. Departure Times to Work, U.S. and Metropolitan Area
Comparisons, 1990
Time U.S. Thirty-Nine
Interval Totals Metropolitan Areas
5:00 A.M. - 6:59 A.M. . . . .26.04% . . . . . .25.49%
7:00 A.M. - 8:29 A.M. . . . .41.87% . . . . . .42.44%
8:30 A.M. - 9:59 A.M. . . . .10.28% . . . . . .11.27%
All Other Departures. . . . .18.85% . . . . . .17.93%
Worked at Home. . . . . . . . 2.96% . . . . . . 2.57%
2-15
Total Vehicles and Vehicles Per Household
Over the past thirty years, privately owned vehicles have become
pervasive in U.S. households. Although automobiles still constitute
the largest component of private vehicles, there has been a dramatic
increase in the number of light trucks, vans, and utility vehicles for
private travel. According to the Bureau of the Census, the
availability of household vehicles in the U.S. from 1960-1990
increased 178%. This is based on 54.8 million vehicles available in
1960 and 152.4 million in 1990.10 Vehicles per household increased
from 1.03 to 1.66 during the period, or about 60%. Vehicles per
worker also rose by a slightly smaller amount with the greatest
increases occurring in the 1970's for both measures.
A number of factors contributed to the 1960-1990 increases. These
include rising household incomes, growth in the number of workers per
household, and decentralization of jobs and residences. The rapid
growth in female workers is probably a leading factor behind the
growth in total vehicles, as two-income households and female-headed
households often acquire a separate vehicle for each worker.
During the 1980-1990 period, U.S. households acquired 17.4% more
vehicles. In 1990, the thirty-nine metropolitan areas accounted for
nearly 72.5 million vehicles in U.S. households, about 48% of all U.S.
household vehicles. California heads all states with over 18 million
vehicles, and the Los Angeles CMSA alone accounted for nearly 8.6
million vehicles, the greatest total among the metropolitan areas.
Texas, New York, Florida and Ohio also had large numbers of household
vehicles.
The Salt Lake City CMSA had the highest rate among metropolitan
areas with 1.88 vehicles per household in 1990. New York City, with
1.20 vehicles per household, had the lowest rate. Vehicles per
household rose, 3.1% increase from 1980 to 1990. In 1990, Wyoming led
all states with 1.98 vehicles per household, compared to a low of 1.22
in New York. Tampa had the highest level of vehicles per worker in
1990, with a ratio of 1.45. The average number of vehicles per person
increased from 0.31 in 1960 to 0.61 in 1990. Thus, more and more,
workers have at least one vehicle available to them at any time. This
means that transit or carpool trips for work are by choice and not
dependency.
Zero Vehicle Households. The share of households without any
vehicles declined by over 46% in the thirty year study period.
Between 1980 and 1990 the absolute number of households with no
vehicles available remained relatively constant, rising by a modest
2%. As a percentage of all households, however, this class declined
by nearly 11%. By 1990, the share of households without vehicles
accounted for just 11.5% of all U.S. households. The New York City
CMSA is an important exception to the general trend, with a zero
vehicle household share of 32% in its metropolitan area. It alone
accounts for about 15% of the U.S. total households without any
vehicle.
-------------------
10The Census Bureau calculates household vehicles in a different way
than the Federal Highway Administration (FHWA), and readers should
take note of these differences in comparing Census data to other
published data. In its annual publication Highway Statistics the FHWA
includes commercial automobiles and commercial light trucks. Also,
some commercial vehicles are kept at home and are likely to be counted
by the Census Bureau as household vehicles. In 1990, the FHWA
reported a total of 185.3 million registered vehicles, of which 143,6
million were automobiles, 37.4 million light trucks, and 4.3 million
were motorcycles.
2-16
One Vehicle Households. From 1960-1990 households with only one
vehicle available grew by less than 3%, remaining at roughly thirty
million over the entire period. Like zero vehicle households,
however, the relative share of such households plummeted by about 41%.
In 1990, households with just one vehicle comprised around 34% of all
U.S. households. The Tampa MSA had the highest share of one vehicle
households in 1990.
In 1960, most households (56%) had only one vehicle, regardless of
the number of adults living in the household. In 1990, with increases
in vehicle availability, one vehicle households were most likely in
areas with a high proportion of single adult households. This seems
to be the case whether it be a young adult, a single parent, or an
elderly widow(er). There is probably a high correlation between one
vehicle households and persons over 65 years old.
Two Vehicle Households. During the 1960-1990 period, two vehicle
households in absolute terms swelled by 241% nationwide, from just
over 10 million to over 34 million. The relative share of these
households also increased almost 97%. In 1990 tabulations, two
vehicle households outnumber all others, accounting for about 37% of
the total. In the 1980's, two vehicle households displayed the most
consistent and strongest growth rates among these categories, rising
over 25% nationwide. By 1990, over 44% of households in New Hampshire
had two vehicles, the highest for any state. New York state, at
26.5%. had the smallest percentage. The Salt Lake City CMSA had the
highest share of two vehicle households in the U.S. in 1990 (42.1%),
while New York City had the lowest share (25.3%).
Three or More Vehicle Households. From 1960-1990, the number of
households with three or more vehicles soared by nearly 1100%,
increasing from about 1.3 million to nearly 16 million households. In
1960, households with three or more vehicles accounted for 2.5% of all
households. By 1990, that share had risen to over 17% of all
households. In 1990, the Salt Lake City CMSA had the highest share of
households with three or more vehicles (22.4%). New Orleans had the
smallest share (10.8%). Among metropolitan areas, growth rates for
households with three or more vehicles were extremely strong in the
1970's, but weakened in the 1980's.
From 1980-1990, U.S. households with three or more vehicles rose in
absolute terms by 13.2%. As a share of all households, however, this
category remained nearly even between 1980 and 1990. In 1990, New
York state had the lowest proportion of households in this category at
around 11%, while Wyoming had a corresponding percentage of over 27%.
2-17
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2-18
Chapter 3
DEMOGRAPHIC CHARACTERISTICS
This chapter describes aspects of population in the thirty-nine
metropolitan areas, including trends for their central county and
suburban counties. The effects of household formation and size are
discussed along with household income, central county size, and urban
population. Major themes from 1960-1990 include declining household
size, increasing numbers of households, and rapid population growth in
Sunbelt and suburban areas.
Population: Areawide, Central County, and Suburban County
From 1960-1990, the U.S. population increased from 179 million to
249 million, a gain of almost 40%. The 1960's produced the highest
growth rate as population increased by 13.3%. Each succeeding decade
produced a slower rate of growth. From 1980-1990, population
increased by only 9.8%, the second lowest growth rate in census
history. The Census Bureau attributed the decline primarily to a
decrease in the rate of childbearing. Increases in immigration did
not offset this low growth rate. Tables 3-1 and 3-1A show the growth
rates for metropolitan areas over one million. Compared to U.S.
totals, growth in the large metropolitan areas was generally stronger,
rising 24% in the 1960's, 7.3% in the 1970's and 11.8% in the 1980's.
Table 3-2 lists the percent changes in the five fastest and five
slowest growing metropolitan areas by decade during the 1960-1990
period. Phoenix was among the most rapidly growing areas in all three
decades. Other metropolitan areas in the Sunbelt also appear more
than once, such as San Diego, Miami, and Houston. Washington, D.C.,
grew 37% in the 1960's, the only northern metropolitan area in this
category. By contrast, metropolitan areas in the slowest growing
areas were consistent across the decades, with Pittsburgh, Buffalo and
Cleveland appearing in each. In 1990, five metropolitan areas had
populations of five million or more. New York City had the most with
17.1 million. Rochester was the smallest of the thirty-nine areas,
with one million inhabitants.
Comparative Growth Rates in Central Counties and Suburban Counties.
Much of the population growth in urban areas over the last thirty
years occurred in the suburban counties. As shown in Tables 3-1 and
3-1A, suburban counties displayed rapid growth compared to central
counties. Table 3-3 below shows the metropolitan areas with the
fastest growing suburban counties between 1960 and 1990. In addition,
it may be argued that those metropolitan areas that are exclusively or
predominantly central counties have had, de facto, similar "suburban"
growth rates. Miami's suburban counties grew by over 200% from 1960-
1980. During the 1980's, Orlando and Cincinnati had the highest
suburban growth rates, with 73% and 66%, respectively. Most other
localities with high suburban growth rates were in the metropolitan
areas of the South and West.1
-------------------
1As noted in Chapter 1, it is necessary to split the 1980-90 time
period in order to account for geographic redefinition.
3-1
Table 3-1. Population (Areawide, Central and Suburban Counties)
1960-1980
Click HERE for graphic.
3-2
Table 3-1. Population (Areawide, Central and Suburban Counties)
1960-1980 (Cont.)
Click HERE for graphic.
3-3
Table 3-1A. Population (Areawide, Central and Suburban Counties)
1980-1990
Click HERE for graphic.
3-4
Table 3-2. Fastest and Slowest Growing Metropolitan Areas,
Percent Changes by Decade
Fastest Growing Populations
1960-1970 1970-1980 1980-1990
Metropolitan Percent Metropolitan Percent Metropolitan Percent
Area Change Area Change Area Change
Miami. . . . . . . 48.8% . .Phoenix. . . 56.0% . .Orlando. . . 53.2%
Los Angeles. . . . 48.3. . .Tampa. . . . 44.2. . .Phoenix. . . 40.6
Phoenix. . . . . . 45.8. . .Houston. . . 43.0. . .Sacramento . 34.7
Houston. . . . . . 38.1. . .Miami. . . . 40.1. . .San Diego. . 34.2
Washington, DC . . 37.0. . .San Diego. . 37.1. . .Dallas . . . 32.6
Slowest Growing Populations
1960-1970 1970-1980 1980-1990
Metropolitan Percent Metropolitan Percent Metropolitan Percent
Area Change Area Change Area Change
Pittsburgh . . . .-0.2%. . Buffalo . . . .-7.9%. .Pittsburgh . -7.5%
Buffalo. . . . . . 3.2 . . Pittsburgh. . .-5.7 . .Buffalo. . . -4.3
Cincinnati . . . . 9.8 . . Cleveland . . .-5.5 . .Cleveland. . -2.6
Cleveland. . . . . 9.8 . . New York City .-5.4 . .Detroit. . . -1.8
New York City. . .10.4 . . St. Louis . . .-2.2 . .New Orleans. -1.4
Fastest Growing Suburban Counties in Large U.S. Metropolitan Areas,
1960-1980 and 1980-1990
1960-1980 1980-1990
Metropolitan . . . .Percent. . . . . . . . . Metropolitan. . . Percent
Area . . . . . . . .Change . . . . . . . . . Area. . . . . . . Change
Miami. . . . . . . .204.9% . . . . . . . . . Orlando . . . . . 72.6%
Denver . . . . . . .155.9. . . . . . . . . . Cincinnati. . . . 66.2
Atlanta. . . . . . .135.0. . . . . . . . . . Dallas. . . . . . 47.9
Los Angeles. . . . .134.7. . . . . . . . . . Atlanta . . . . . 41.1
Portland . . . . . .127.4. . . . . . . . . . Los Angeles . . . 41.0
3-5
Figure 3-1 illustrates the relationship in 1990 between land area
and population in central counties of the metropolitan areas. Only
five areas have 50% or more of their total land area in central
counties (San Diego, Phoenix, San Antonio, Buffalo, and Miami). In
contrast, nineteen metropolitan areas have 50% or more of their total
population in central counties. Thus, in most metropolitan areas,
central counties still have a disproportionately high share of the
total population, but a disproportionately low share of total land
area. The data also suggest the higher population densities that
exist in central counties compared to suburban counties.
Figure 3-2 shows the effects of the 1983 geographic change on
population at the areawide level for the group of thirty-nine
metropolitan areas. The two values for 1980 reflect the geographic
revisions. As may be confirmed in Tables 3-1 and 3-1A, suburban
counties accounted for most of the areawide growth, almost a 14%
increase from 1980-1990, continuing the high rates established in the
previous two decades.
Figure 3-2. Effect of 1983 Geographic Revision
On Area Population
Click HERE for graphic.
Viewing the entire thirty year period, many older metropolitan
areas lost more than 20% of their central county population
(Philadelphia, Detroit, Washington, D.C., St. Louis, Baltimore, and
New Orleans). Central counties with the highest growth rates are
concentrated in the West and South. The central counties of five
metropolitan areas grew by over 100% from 1960 to 1990. The rates,
however, are somewhat overstated in metropolitan areas such as Phoenix
and San Diego which are entirely central county. In the 1980's, only
Orlando, Charlotte, Sacramento, and Tampa registered gains of 25% or
better (excluding 100% central county areas).
3-6
Figure 3-1. Central County Comparisons, 1990 - Percent Areawide
Population & Land
Click HERE for graphic.
3-7
Fourteen metropolitan areas had net decreases in central county
population during the 1960 to 1990 period (Table 3-4). St. Louis had
the largest loss in central county population, a decline of 47.1%.
Several others lost over twenty percent of central county populations.
Generally, the 1970's appeared to mark the height of losses in central
county populations (Figure 3-3). Indeed, twenty-one of the
metropolitan areas had percent decreases during the 1970's. In the
1980's, however, central county populations grew in eight areas that
had previously declined in the 1970's. These were New York City, San
Francisco, Boston, Atlanta, Minneapolis, Kansas City, Indianapolis,
and Providence. Without the influence of immigration, it is unlikely
that Central County population would have increased in the 1980's.
From 1980 to 1990 the central counties averaged only a 9.2% population
increase, while the suburban counties averaged 13.8%.
Despite some increases in central counties populations during the
1980's, suburban populations are accounting for increasingly higher
shares of overall area populations. During that time, thirty-three
central counties had net losses in share of metropolitan area
population (Table 3-5, Figure 3-4). The loss in central county share
for seven metropolitan areas exceeded ten percent.
Household Formation and Size. From 1960-1990 the number of
households in the U.S. increased nearly 75%, from 53 million to 92
million. Meanwhile, household size was declining. In 1960, the
average U.S. household had 3.33 persons. The average household had
3.11 persons in 1970, 2.75 persons in 1980, and 2.63 persons in 1990.
This represented a decline of over 20% during the thirty year period.
The 1970-1980 period accounted for not only the largest percent
increase, in total households (26.7%), but also the largest percent
decline in household size (11.58%). This pattern of more but smaller
households seems firmly in place.
For the thirty-nine metropolitan areas, there was wide variation in
1990 in household size, ranging from 3.09 persons per household in
Salt Lake City to 2.37 in Tampa. Most of these areas showed declines
in households between 1980 and 1990. One exception to this trend
should be noted. California's four large metropolitan areas (Los
Angeles, San Francisco, San Diego, and Sacramento) had increasing
household size from 1980 to 1990. Los Angeles had the highest growth,
increasing from 2.78 to 2.96 between 1980 and 1990, a 6.5% rise. In
California, there are strong, local influences affecting demographic
measures, such as new immigrant households and higher housing costs.
Figure 3-5 and Table 3-6 show demographic characteristics for
persons per household, vehicles per household and workers per
household. In this report, workers per household is calculated by
dividing total workers by total households. Because total workers
includes workers who live in group quarters and not in households, the
number is slightly overstated. The largest discrepancy is in areas
with high military and college dormitory group quarters population.
While persons per household reflects very little variation among the
metropolitan areas, vehicles per household and workers per household
show wider variation due to differing costs of vehicle ownership,
conditions that affect labor force participation, availability of
transportation alternatives and other local conditions.
Urban Populations. The Census Bureau categorizes populations
according to urban and rural. Urban populations include those living
in officially designated "urbanized areas" (UZA's), plus those living
in urban areas outside UZA's. Rural population includes rural farm
and rural nonfarm. From 1960 to 1990, the urban population of the
United States rose from 54.1 million to 61.7 million, an increase of
49.3%. The largest increase was in the 1960's when urban population
rose 19.5%. As a share of the total, urban population represented
69.9% in 1960, 73.6% in 1970, 73.7% in 1980, and 75.2% in 1990.
3-8
Table 3-4. Central County Population, 1960-1990
Click HERE for graphic.
3-9
Figure 3-3. Changes in Central County Population 1960-1990
Click HERE for graphic.
3-10
Table 3-5. Relationship of Central County to Areawide Population,
1980-1990
Click HERE for graphic.
3-11
Figure 3-4. Central County Share of Area Population - Percent Change
1980-1990
Click HERE for graphic.
3-12
Figure 3-5. 1990 Household Ratios
Click HERE for graphic.
3-13
In the thirty-nine metropolitan areas, urban and rural population
for 1990 are displayed in Table 3-6. The Miami metropolitan area had
the highest percentage of population (98.9%) classified as urban,
while Charlotte showed the fewest (68.7%) people living in urban
areas. The average for the entire group of large metropolitan areas
was 91.6%, compared to 75.2% for the U.S. as a whole. In sum, the
data depict a country with an increasingly urban population, and large
metropolitan areas that are now overwhelmingly urban.
Household Income. Table 3-7 shows 1990 data for household income.
The top five areas for median household income are Washington, D.C.,
San Francisco, Hartford, Boston, and New York. Thus, while Sunbelt
regions have the highest rates of population growth, the older
Northeastern metropolitan areas continue to have the highest household
incomes. This may be due to the combination of higher local wages and
more workers per household. In Washington, D.C., over 20% of the
households had 1990 incomes of $75,000 or more. At the lower end of
the group are New Orleans, Tampa, San Antonio and Pittsburgh. In New
Orleans, over 30% of households earned less than $15,000. In 1990,
the median household income in Washington, D.C. was $46,856, while the
median household income in New Orleans was $24,442.
Trip volume and mode choice decisions reflect household income
levels and geographic location of income groups. Workers in certain
economically sensitive industries and occupations may display
different commuting patterns than those in more stable industries.
Lower incomes mean fewer vehicles available per household, and thus
fewer drive alone commute trips.
3-14
Table 3-6. Demographic Ratios and Urban/Rural Population
Percentages, 1990
Metro- Persons Vehicles Workers Percent Percent
politan Per Per Per Urban Rural
Area Household Household Household* Population Population
NYC 2.67 1.20 1.29 95.7% 4.3%
LOS 2.91 1.74 1.39 97.4% 2.6%
CHI 2.72 1.49 1.32 96.0% 4.0%
SFC 2.61 1.73 1.37 96.1% 3.9%
PHI 2.66 1.49 1.30 89.0% 11.0%
DET 2.67 1.66 1.21 88.4% 11.6%
BOS 2.61 1.54 1.39 87.1% 12.9%
WAS 2.62 1.67 1.52 91.5% 8.5%
DAL 2.64 1.74 1.36 92.6% 7.4%
HOU 2.75 1.65 1.32 89.7% 10.3%
MIA 2.58 1.49 1.21 98.9% 1.1%
ATL 2.64 1.80 1.40 80.9% 19.1%
CLE 2.56 1.62 1.17 90.1% 9.9%
SEA 2.49 1.81 1.30 89.9% 10.1%
SDG 2.69 1.75 1.39 95.2% 4.8%
MIN 2.58 1.74 1.40 89.9% 10.1%
STL 2.59 1.66 1.24 87.9% 12.1%
BAL 2.64 1.57 1.35 87.2% 12.8%
PIT 2.46 1.45 1.07 80.9% 19.1%
PHX 2.59 1.65 1.23 96.4% 3.6%
TAM 2.32 1.52 1.05 89.2% 10.8%
DEN 2.46 1.77 1.31 94.2% 5.8%
CIN 2.61 1.69 1.25 85.1% 14.9%
MIL 2.61 1.59 1.28 89.6% 10.4%
KSC 2.55 1.72 1.28 89.2% 10.8%
SAC 2.60 1.78 1.23 87.9% 12.1%
POR 2.52 1.75 1.26 84.7% 15.3%
NFK 2.69 1.68 1.41 94.8% 5.2%
COL 2.54 1.71 1.29 80.9% 19.1%
SAT 2.82 1.63 1.26 91.2% 8.8%
IND 2.56 1.71 1.30 82.7% 17.3%
NRL 2.67 1.41 1.13 93.2% 6.8%
BUF 2.51 1.47 1.15 85.4% 14.6%
CHA 2.58 1.80 1.37 68.7% 31.3%
PRO 2.57 1.30 1.27 87.1% 12.9%
HAR 2.56 1.72 1.37 80.3% 19.7%
ORL 2.60 1.71 1.38 90.3% 9.7%
SLC 3.04 1.88 1.38 98.4% 1.6%
ROC 2.58 1.64 1.28 70.6% 29.4%
*Total workers divided by total households. Total workers includes
workers who live in group quarters.