(Based on comparable methodology)
|Value-added by all transportation services||GDP (billions of 1997 dollars)|
|Billions of 1997 dollars||Percent of GDP|
KEY: NA = Not applicable.
NOTES: Value-added by all transportation services is different in 1992 and 1997 due to a difference in in-house transportation measurement. In 1992, in-house transportation includes in-house truck and bus transportation; while in 1997, it includes in-house air, rail, truck, and water transportation.
SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics.