|Number ($ millions)||Percent||Number (thousands)||Percent||Number (millions)||Percent|
|Air (including truck and air)||1,778||1.4||31||Z||42||0.1|
|Parcel, U.S. Postal Service, or courier service||11,956||9.7||317||0.1||224||0.5|
|Truck and rail intermodal combination||S||S||S||S||S||S|
|Truck and water||S||S||S||S||24||Z|
|Rail and water||116||0.1||3,490||1.4||1,499||3.1|
|Other multiple modes||S||S||S||S||S||S|
|Other and unknown modes||2,970||2.4||3,855||1.5||S||S|
KEY: S = data do not meet publication standards because of high sampling variability or other reasons; Z = zero or less than 1 unit of measure.
NOTE: The Commodity Flow Survey covers business establishments in mining, manufacturing, wholesale trade, and selected retail industries. The survey also covers selected auxiliary establishments (e.g., warehouses) of in-scope multiunit and retail companies. The survey excludes establishments classified as farms, forestry, fisheries, governments, construction, transportation, foreign establishments, services, and most establishments in retail. Due to industry-wide reporting problems, shipments by oil and gas extraction establishments are also excluded.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics and U.S. Department of Commerce, U.S. Census Bureau, 1997 Commodity Flow Survey, Washington, DC: 1999, available at http://www.bts.gov/ntda/cfs/cfs97od.html as of Nov. 2, 2001.