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 |
Value — standard error |
Tons — standard error |
Ton-miles (1) — standard error |
|||
|---|---|---|---|---|---|---|
| 2012 | 2007 | 2012 | 2007 | 2012 | 2007 | |
| All modes | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Single modes | 0.2 | 0.4 | 0.2 | 0.4 | 0.9 | 0.8 |
| Truck (2) | 0.4 | 0.5 | 1.0 | 0.7 | 1.2 | 1.3 |
| For-hire truck | 0.3 | 0.5 | 0.8 | 0.7 | 1.2 | 1.0 |
| Private truck | 0.3 | 0.3 | 0.4 | 0.5 | 0.1 | 0.3 |
| Rail | 0.2 | 0.2 | 1.0 | 0.8 | 2.3 | 2.1 |
| Water | 0.3 | 0.1 | 0.6 | 0.3 | 1.0 | 0.6 |
| Inland water | 0.3 | 0.1 | 0.6 | 0.3 | 0.7 | 0.6 |
| Great Lakes | Z | S | 0.1 | 0.0 | 0.1 | 0.1 |
| Deep sea | 0.1 | 0.0 | 0.2 | 0.0 | 0.2 | 0.2 |
| Multiple waterways | 0.1 | X | 0.1 | X | 0.3 | X |
| Air (includes truck and air) | 0.1 | 0.2 | Z | 0.0 | Z | 0.0 |
| Pipeline (3) | 0.4 | 0.2 | 0.6 | 0.4 | S | S |
| Multiple modes | 0.2 | 0.3 | 0.2 | 0.2 | 0.9 | 0.8 |
| 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 |
| Other modes | Z | 0.2 | 0.1 | 0.3 | Z | 0.1 |
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.