a In-house transportation consists of the services provided by non-transportation industries for their use. It includes privately owned and operated vehicles of all body types, used primarily on public rights of way, and the supportive services to store, maintain, and operate those vehicles.
b For-hire transportation consists of the services provided by transportation firms to industries and the public on a fee-basis. Other for-hire transportation includes: transit and ground passenger transportation, including State and local government passenger transit; sightseeing transportation and transportation support; courier and messenger services; and warehousing and storage.
SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics.