NOTES: For consistency, aviation passenger-miles of travel (pmt) includes air carrier aviation only, as general aviation pmt 2002 data were not available when this report was prepared. See table 1-1 in appendix B for definitions.
Percentages may not add to 100 because of independent rounding.
SOURCES: Passenger-miles—U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, National Transportation Statistics 2004, table 1-37, available at http://www.bts.gov/, as of January 2005. GDP—Based on chained 2000 dollar data from U.S. Department of Commerce (USDOC), Bureau of Economic Analysis, National Income and Product Accounts, summary GDP table, available at http://www.bea.doc.gov/, as of December 2004. Population—USDOC, U.S. Census Bureau, Statistical Abstract of the United States, Section 1: Population, table No. 2. Population: 1960 to 2003, available at http://www.census.gov/, as of May 2005.