Table B-1c. Estimated Standard Errors for Shipment Characteristics by Mode of Transportation for the United States: Percentage of Total for 2012 and 2007
(Estimates are based on data from the 2012 and 2007 Commodity Flow Surveys)
|Mode of transportation||
|Air (includes truck and air)||0.1||0.2||Z||0.0||Z||0.0|
|Parcel, U.S. Postal Service, or courier||0.2||0.3||Z||0.0||Z||0.0|
|Truck and rail||0.1||0.1||0.1||0.1||0.4||0.3|
|Truck and water||Z||0.1||0.1||0.2||0.7||0.5|
|Rail and water||Z||0.0||0.1||0.1||0.3||0.4|
|Other multiple modes||Z||0.1||Z||0.1||Z||0.2|
KEY: X = Not applicable.
Z = Rounds to zero.
(1) Ton-miles estimates are based on estimated distances traveled along a modeled transportation network. See “Mileage Calculations” section for additional information.
(2) “Truck” as a single mode includes shipments that were made by only private truck or only for-hire truck.
(3) Estimates for pipeline exclude shipments of crude petroleum (SCTG 16).
NOTES: The Introduction and appendixes give information on confidentiality protection, sampling error, nonsampling error, sample design and definitions. Links to this information on the Internet may be found at <www.census.gov/cfs>.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics and U.S. Department of Commerce, U.S. Census Bureau, 2012 Economic Census: Transportation Commodity Flow Survey, December 2014.