Figure 2,
Increases in Passenger-Miles of Travel (PMT) and Factors Affecting Travel Demand: 1975–2000,
(Percent Increase),
,Percent
PMT,87.51
Automobiles,67.32
Income,64.25
workers,52.12
households,48.31
Population,30.62
"SOURCES: U.S. Department of Commerce, U.S. Census Bureau, Statistical Abstract of the United States: 2001 (Washington, DC: 2002); various sources as cited in U.S. Department of Transportation, Bureau of Transportation Statistics, National Transportation Statistics 2001 (Washington, DC: 2002); and various sources as compiled by the Bureau of Transportation Statistics.",