Gross domestic product is the market value of goods and services produced by labor and property in the United States. The U.S. Bureau of Economic Analysis estimates GDP for each quarter and releases new statistics every month. Quarterly GDP data are seasonally adjusted at annual rates.

Heavy trucks include trucks with more than 14,000 pounds gross vehicle weight. Prior to the 2003 Benchmark Revision heavy trucks were more than 10,000 pounds. The U.S. Bureau of Economic Analysis releases auto and truck sales data, which are used in the preparation of estimates of personal consumption expenditures.

Employed persons include people aged 16 years and older in the civilian noninstitutional population who did any work at all as paid employees; worked in their own business, profession, or on their own farm, or worked 15 hours or more as unpaid workers in an enterprise operated by a member of the family; and all those who were not working but who had jobs or businesses from which they were temporarily absent. The Bureau of Labor Statistics produces industry estimates of nonfarm payroll employment as part of the Current Population Survey.

Percentage of flights arriving on-time. A flight is on-time if it arrives within 15 minutes of the schedule arrival time. Data are available for those carriers that had at least 1% of domestic enplanements in the previous year. The last 25 months of data include only carriers that reported in each of the last 25 months to retain comparability. Earlier data includes all reporting carriers. A scheduled operation consists of any nonstop segment of a flight. The Bureau of Transportation Statistics air collects performance data from U.S. air carriers and international carriers operating within the U.S.

Rail carload traffic is comprised of mostly bulk commodities, such as coal and agricultural products. The Association of American Railroads releases data on carloads and intermodal units originated by U.S. railroads on a weekly and monthly basis.

General aviation fatalities include private aviation operations and excludes Federal Aviation Regulation (FAR) Part 121 (Air Carriers), 129 (Foreign), 135 (On-Demand), and Non-U.S./Commercial operations. The National Transportation Safety Board releases aviation fatality data in the Aviation Accident Database.

The Bureau of Transportation Statistics calculates this value using system data provided by CitiBike NY/JC (New York, NY and Jersey City, NJ), Capital Bikeshare (Washington, DC area), Divvy (Chicago, IL), Bay Wheels (San Francisco, CA), and Blue Bikes (Boston, MA area).

Passengers transported on Amtrak and Alaska Railroad operations. The Federal Railroad Administration collects accident/incident and operational data from railroads. Tourist and commuter railroad are excluded.

Personal spending on transportation services includes spending on motor vehicle services, such as maintenance and repair, and public transportation, including rail transportation, intercity buses, taxicabs and ride sharing services, intracity mass transit, air transportation, and water transportation. The Bureau of Economic Analysis estimates personal consumption expenditures, the primary measure of consumer spending on goods and services in the U.S. economy, for each quarter and releases new statistics every month. Quarterly PCE data are seasonally adjusted at annual rates to remove the effects of normal seasonal variation.

National Highway Traffic Safety Administration releases data on highway fatalities in the Fatality Analysis Reporting System (FARS). Data for the most recent year are preliminary estimates.