Average Fuel Efficiency of U.S. Light Duty Vehicles (metric)

KEY: CAFE = Corporate Average Fuel Economy; GVWR = gross vehicle weight rating; kmpl = kilometers per liter; R = revised; U = data are not available.

^a Data from 2007 were calculated using a new methodology developed by FHWA. Data for these years are based on new categories and are not comparable to previous years. The new category Light duty vehicle, short wheel base replaces the old category Passenger car and includes passenger cars, light trucks, vans and sport utility vehicles with a wheelbase (WB) equal to or less than 121 inches. The...

Energy Intensity of Certificated Air Carriers, All Services (Metric)

KEY:  R = revised.

^a U.S. owned carriers only. Operations of foreign-owned carriers in or out of the United States not included.

U.S. Ton-Miles of Freight

KEY: R= revised; U = data are not available.

^a Incudes Freight, Express, and Mail. 

^b Estimates from 1980 to 1989 come from the Association of American Railroads using ton mile values from the Surface Transportation Board’s Waybill Sample. The Waybill Sample represents all major U.S. railroads, including all Class I railroads and several short-line railroads.

^c Foreign water traffic is only measured for their travel on U.S. waterways, based on distance from coastal entrance channels to ports and waterways,...

Passengers Boarded at the Top 50 U.S. Airports

^a The 2015 and 2024 totals for the top 50 airports may not sum from the individual airports because some top 50 airports in 2025 were not in the top 50 in earlier years.

^b All U.S. airports consists of 1,258 airports as of 2025 and includes Puerto Rico, U.S. Virgin Islands and U.S. Pacific Trust Territories and Possessions.

Principal Means of Transportation to Work

KEY: NA = not applicable.

^a From 2004 onward, the Carpool categories are 2-person and 3+ person; 4+ person is the sum of 4-person, 5-6 persons, and 7+ persons from the source data.

^bPublic transportation refers to bus, streetcar, subway, railroad, and elevated trains for years 1989-2001, and includes ferryboats from 2002-14.

^c From 1989 to 2001, Bicycle data are included under Motorcycle.

^d Other means include ferryboats, surface trains, and van...

U.S. Passenger-Miles

KEY: N = data do not exist; R = revised; U = data are not available.

^a Data from 2007 were calculated using a new methodology developed by FHWA. Data for these years are based on new categories and are not comparable to previous years. The new category Light duty vehicle, short wheel base replaces the old category Passenger car and includes passenger cars, light trucks, vans and sport utility vehicles with a wheelbase (WB) equal to or less than 121 inches. The new category Light duty vehicle, long wheel base replaces Other 2-axle,...

Petroleum Oil Spills Impacting Navigable U.S. Waterways

KEY: N = data do not exist; R = revised.

^a Other vessels include commercial vessels, fishing boats, freight barges, freight ships, industrial vessels, oil recovery vessels, passenger vessels, unclassified public vessels, recreational boats, research vessels, school ships, tow and tug boats, mobile offshore drilling units, offshore supply vessels, publicly owned tank and freight ships, as well as vessels not fitting any particular class (unclassified).

^bOther nonvessel sources include deepwater ports, designated...

U.S. Carbon Dioxide Emissions from Energy Use by Sector

KEY:  CO2 = carbon dioxide; R = revised; Z = a value of zero, or value too small to report.

^a  Hydrocarbon Gas Liquids (HGL) includes ethane, propane, normal butane, isobutane, and natural gasoline, and their associated olefins. Excludes Liquified Natural Gas (LNG). 

Air Pollution Trends in Selected Metropolitan Statistical Areas

KEY:  AQI = Air Quality Index; R = revised.

Estimated U.S. Emissions of Sulfur Dioxide

KEY: P = preliminary; R = revised.

^aIndustrial processes consists of chemical and allied product manufacturing, metals processing, petroleum and related industries, and other industrial processes; solvent utilization; and storage and transport.