The Transportation Satellite Accounts (TSAs) provide a means for measuring the contribution of transportation services to the national economy. Prior to the TSAs, the magnitude of transportation services had long been underestimated, as most national measures counted only the value of for-hire services. Measurement of services provided only by for-hire firms misses the sizable contribution of transportation services that take place within nontransportation industries (termed as in-house transportation) (see box A for the definition of for-hire and in-house transportation).
To more accurately measure transportation services, the Bureau of Transportation Statistics (BTS) of the U.S. Department of Transportation and the Bureau of Economic Analysis (BEA) of the U.S. Department of Commerce, jointly developed the Transportation Satellite Accounts (TSAs). The TSAs, as a supplement to the U.S. Input-Output (I-O) Accounts, measure the contribution of both for-hire and in-house transportation. The TSAs include all of the for-hire transportation industries reported in the summary level U.S. I-O accounts (air, rail, truck, passenger and group transportation, pipeline, and other transportation and support services) and the five created in-house transportation modes (air, rail, water, truck, and household transportation). Four of the five in-house transportation modes are related to business activities (air, rail, water, and truck transportation) and one, household transportation, is related to household activity. Household transportation covers transportation provided by households for their own use through the use of an automobile and is a new component of the TSAs.
The TSAs were developed using benchmark I-O account data published by BEA. The benchmark I-O data provides detailed information on the commodity inputs used by each industry to produce its output, the commodities produced by each industry, and the commodities used by final consumers. Data are released for every fifth year. For years in-between, BEA releases annual I-O account data that provides the same information as the benchmark data but in less detail.
The annual TSAs were developed as an extension of the benchmark TSAs to provide the most current estimate of the contribution of transportation services to the economy as possible. They are based on the annual I-O accounts published by BEA. Because the annual I-O accounts do not contain the detail of the benchmark I-O accounts, the 2002 benchmark accounts are used in conjunction with the annual accounts to provide estimates of in-house transportation for the years 2003 to 2006. Information on how the 2002 benchmark accounts are used to create the annual I-O accounts can be found at this page. Annual TSAs are presented here for the years 2002 through 2006 along with data from the benchmark 2002 TSAs.
The TSAs consist of four tables: the make, use, direct requirements, and total requirements table. These tables are available on the Bureau of Transportation Statistics' website. The following provides a brief summary of the information contained in these tables.
Transportation services contributed about $466.5 billion of value-added in 2002, or about 3.9 percent of gross domestic product (GDP). The value-added by transportation services grew from about 3.9 percent of gross domestic product (GDP) in 2002 to 4.6 percent in 2006. This growth follows an increase in the absolute value added by business related transportation. The contribution of household transportation declined slightly. (See table 1)
With regards to the value added by business-related transportation,
The value-added by in-house air, rail, truck, and water transportation services produced and consumed by businesses was $57.3 billion in 2002 and $104.9 billion in 2006. Value-added by in-house air, rail, truck, and water transportation services produced and consumed by businesses grew from 2002 to 2006 from 0.48 to 0.75 percent of GDP. This growth derives primarily from the increase in the value-added by in-house truck transportation, which increased from 0.37 percent to 0.58 percent of GDP. The value added by all other in-house transportation related to business grew, but not as significantly. Of all in-house modes, truck transportation contributes the most value.
The value-added by for-hire transportation air, rail, truck, and water transportation was $162.9 billion in 2002 and $230.2 billion in 2006. In 2002, the four modes accounted for 1.37 percent of GDP; in 2006, they accounted for 1.65 percent. Combined value-added by for-hire air, rail, truck, and water transportation grew at approximately the same rate as the four in-house counterparts. The value added by for-hire air, rail, truck, and water transportation grew by 0.27 percentage points, whereas the value added by in-house air, rail, truck, and water transportation grew by 0.28 percentage points.
With regards to the value added by household transportation,