|Air, certificated, domestic, all services||Light duty vehicle||Bus||Transit||Amtrak|
U = unavailable, comparable data are unavailable due to a change in FHWA estimation methodology.
NOTES: Light duty vehicle includes short wheel base passenger cars, light trucks, vans, and sport utility vehicles (SUVs) with a wheel base equal to or less than 121 inches and long wheelbase large passenger cars, pickup trucks, vans, and SUVs with a wheel base longer than 121 inches. Bus and demand response are included in both Bus and Transit, which results in some double counting. Amtrak does not include contract commuter passengers. The data above may not be consistent with other sources, particularly data that are revised on an irregular or frequent basis. Different Vehicle occupancy rates were used to estimate passenger miles for Light duty vehicles and Bus beginning with 2009.
SOURCES: Various sources as cited in U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, National Transportation Statistics, table 1-40, available at http://www.bts.gov/publications/national_transportation_statistics/ as of August 2013.