September 11, 2008

Washington, DC

Demographic Trends Affecting Transportation in the U.S.

Robert Puentes

Realities on the ground have changed dramatically1

Demographic Trends Affecting Transportation in the U.S.

These changes have 3 main spatial effects on the American landscape2Together these patterns have a series of important implications.3

Population Growth Immigration Internal MigrationAging Household Formation

-100,000

0

100,000

200,000

300,000

400,000

500,000

600,000

Nigeria

Pakistan

Philippines

Banglad

eshIndiaBrazil U.S.

Canada

Indonesia

Norway U.K.

FranceChinaSpain

Netherla

ndsKoreaAustria

Denmark Ita

lyGerm

any

Czech

HungaryJap

anPolan

d

-20%

0%

20%

40%

60%

80%

100%

120%

Percent and absolute population growth, 2005-2050

Absolute growth

Percent growth

Source: U.N. Population Division

Unlike most European nations and Japan, the U.S. will continue to grow at a considerable rate.

0

2

4

6

8

10

12

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045

Legal Undocumented

Temprorary (Net) Projected

Total foreign-born, in millions, 1960-2050

Source: Jeffrey S. Passel, 2006

The increase in population will continue to be fueled in part by an enormous wave of immigration.

Mill

ions

Percent growth in U.S. total and senior populations by

decade, 1970–2030

0%

5%

10%

15%

20%

25%

30%

35%

40%

1970-1980 1980-1990 1990-2000 2000-2010 2010-2020 2020-2030

Age 65+ Total

Source: Frey, 2007

This immigration is essential to offset another major demographic trend: the aging of the baby boom generation.

US age distribution, by race, 2020

(Age pyramid moves from the elderly at the top to youths at the bottom)

Source: Census

However, since minorities have younger age structures than whites, the nation’s population pyramids will look quite different.

Male Female

\

Male Female

Male Female Male Female

Whites Hispanics

Blacks API/AI

0

2

4

6

8

10

12

14

1-pers

on household

Single w/ k

idsMarr

ied w

/ kids

Married

no kids

Other family

Nonfamily

Mill

ions

2.0

2.5

3.0

3.5

4.0

4.5

5.0

19001920194019601980200020202040

Household size is declining sharply, primarily due to the increases in single person and parent households.

Sources: (1) Yi, Land, Wang, and Danan; (2) Frey and Berube, 2003 and updated

Persons per household, 1900-2050

Absolute change in households, 1980-2005

U.S. population growth, 1900-2005

Source: Census

0%

5%

10%

15%

20%

25%

30%

35%

40%

1900

1905

1910

1915

1920

1925

1930

1930

1940

1945

1950

1955

1960

1965

1970

1975

1980

1985

1990

1995

2000

2005

2010

2015

2020

2025

South

West

MidwestNortheast

But these growth trends are highly variable across the country. The story of rapid growth in the U.S. is largely confined to the South and the West.

Realities on the ground have changed dramatically1These changes have 3 main spatial effects on the American landscape2Together these patterns have a series of important implications.3

Demographic Trends Affecting Transportation in the U.S.

First, rather than dispersing randomly all this population and economic activity is shifting and re-aggregating within and between major metropolitan areas.

Metropolitan areas have become the engines of national prosperity.

Second, these mega-trends are revaluing the assets of the cities and urban cores within metropolitan areas.

These forces have reconfirmed the primacy and centrality of place.

Third, America's metropolitan areas have become exceedingly complex and have moved well beyond the conventional city versus suburb divide.

These are not your parent’s suburbs

Together these patterns have a series of important implications.3

Demographic Trends Affecting Transportation in the U.S.

3

Realities on the ground have changed dramatically1These changes have 3 main spatial effects on the American landscape2

“Never make predictions, especially about the future.”

-Casey Stengel

Source: Nelson, “Toward a New Metropolis,” 2004

1. What will be the impacts on residential location?

The pressure will be on existing places—especially cities and first suburbs—to accommodate new growth.

Source: NAR, 2004

Exurbs26%

Suburbs20%

Urban Areas54%

Preference for next residential location,

2004

2. How will transportation be impacted by changing household formation?

Demand for higher-density housing in

transit zones could far outstrip the supply

of this kind of housing.

4

6

8

10

12

14

16

2000 2005 2010 2015 2020 2025

Projected Demand: Housing Units in Transit Zones

14.6 million

Source: Center for Transit-Oriented Development, Hidden in Plain Sight and Harvard, State of the Nation’s Housing

3. What will be the impacts of continued diversity?

The nation will be majority minority by 2050 and nearly 90 percent of the population growth in 2050 will be the result of

post 2000 net immigration.

Immigrants are more likely to carpool. But

their high levels of transit use decline over

time.

Blacks and Hispanics together make up nearly half of the

nation’s transit users

0%

10%

20%

30%

40%

50%

Under15

15-24 25-34 35-44 45-54 55-64 65-74 75+

Age Group

4. What will be the impacts of the aging of the population?

Percent of metro residents residing in central cities by age

group, 2000

The location preferences of the elderly do not suggest a “back-to-the-city” movement.

LOSS GAIN

5. What will be the impacts of national migration shifts?

The challenge will be maintaining investments in declining areas without overbuilding.

Projected population change, by county, 2000-2050

Demographics will not be the only determinant of our future, of course. Globalization, climate change, technological innovation, freight, energy concerns, and public policy are key.

Yet we have an enormous opportunity now to shape our nation's metropolitan future.

September 11, 2008

Washington, DC

Demographic Trends Affecting Transportation in the U.S.

Robert Puentes