Introduction
Introduction
America's transportation system has changed along with the nation's society and economy. The following table puts those changes in perspective:
| Context | 1980 | 2001 |
|---|---|---|
| Resident population (thousands) | 226,542 | 284,797 |
| Total area (thousands of square miles)a | 3,619 | 3,718 (1990) |
| Total civilian labor force (thousands) | 106,940 | 141,815 |
| Real gross domestic productb | $4.9 trillion | $9.2 trillion |
| Median household incomeb, d | $32,661 (1984) | $38,426 |
| Average household incomeb, c, d | $34,189 (1984) | $43,362 |
| Average household expendituresb, c, d | $32,020 (1984) | $36,070 |
| Number of households (thousands) | 80,776 | R105,480 (2000) |
| Average life expectancy (years) | 73.7 | P76.9 (2000) |
a 1980 data include the Great Lakes and inland and coastal water. 1990 data include inland water only. The Census Bureau tabulates area data for the decennial census years only.
b Expressed in 1996 chained dollars (see Glossary for definition).
c Earliest year available is 1984.
d BTS computations, Nov. 15, 2002.
Key: P = preliminary data; R = revised.
Sources: Population, area, number of households-U.S. Department of Commerce (USDOC), Census Bureau, Statistical Abstract of United States: 2000, available at http://quickfacts.census.gov/qfd/states/00000.html; GDP- USDOC, BEA; median household income-USDOC, Census, available at www.census.gov/hhes/www/income/histinc/ie1.html; average household income and expenditures, employment-U.S. Department of Labor, BLS, available at http://www.bls.gov/cex; life expectancy-Centers for Disease Control and Prevention, available at www.cdc.gov.