|Oil and natural gas pipeline||879.2||20.1|
SOURCES: U.S. Department of Transportation (USDOT), Research and Innovative Technology Administration, Bureau of Transportation Statistics (BTS), calculations using data from various sources as follows: Air—USDOT, BTS, Air Carrier Traffic Statistics Monthly (Washington, DC:1990-2002 issues), p. 2, line 3, Freight, Express, and Mail Revenue Ton-Miles; and USDOT, Federal Aviation Administration supplementary statistics. Truck—USDOT, BTS, Transportation Statistics Annual Report 2000 (Washington, DC: 2001), p. 124, table 2; U.S. Army Corps of Engineers, Waterborne Commerce Statistics Center, U.S. Waterborne Container Traffic by Port; USDOT, BTS, Border Crossing / Entry Data, U.S.-Canada, tables 1a, b, and c; U.S.-Mexico, table 1; USDOT, Federal Highway Administration, Highway Statistics 2002 (Washington, DC: 2003), table VM-1. Rail—Surface Transportation Board, Carload Waybill Sample, 1990-2002; Transport Canada, Transportation in Canada, Addendum (Ottawa, Ontario: 1990-2002 issues), table A6-10; Association of American Railroads, Railroad Facts (Washington, DC: 1991-2002 issues), p. 36. Water—U.S. Army Corps of Engineers, Waterborne Commerce of the United States (Washington, DC: 2002), part V, section 1, table 1-4, Total Waterborne Commerce. Oil pipeline—Association of Oil Pipelines, Shifts in Petroleum Transportation (Washington, DC: 2002), table 1. Natural gas pipeline—U.S. Department of Energy (DOE), Energy Information Administration (EIA), Annual Energy Review 2002 (Washington, DC: 2003), table 6.5; and DOE, EIA, International Energy Annual 2001 (Washington, DC: 2003), table C-1.