Table B-1a. Estimated Measures of Reliability for Hazardous Material Shipment Characteristics by Mode of Transportation for the United States: 2012
(Estimates are based on data from the 2012 Commodity Flow Survey)
| Mode of transportation | Value | Tons | Ton-miles (1) | Average miles per shipment— coefficient of variation of number | |||
|---|---|---|---|---|---|---|---|
| Coefficient of variation of number | Standard error of percent of total | Coefficient of variation of number | Standard error of percent of total | Coefficient of variation of number | Standard error of percent of total | ||
| All modes | 3.1 | 0.0 | 3.7 | 0.0 | 6.2 | 0.0 | 7.8 |
| Single modes | 3.1 | 0.2 | 3.7 | 0.3 | 6.0 | 3.4 | 7.4 |
| Truck (2) | 3.6 | 1.8 | 3.7 | 2.1 | 6.0 | 1.5 | 6.2 |
| For-hire truck | 4.5 | 2.2 | 4.9 | 2.2 | 5.0 | 1.3 | 8.3 |
| Private truck | 7.6 | 1.3 | 7.5 | 1.4 | 11.2 | 1.0 | 9.1 |
| Rail | 7.7 | 0.2 | 6.2 | 0.2 | 6.9 | 1.9 | 2.9 |
| Water | 24.3 | 2.0 | 28.2 | 2.6 | 17.4 | 2.6 | 15.6 |
| Inland water | 26.3 | 1.7 | 30.6 | 2.3 | 28.7 | 2.4 | S |
| Great Lakes | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Deep sea | 38.0 | 0.5 | 36.9 | 0.6 | 36.7 | 2.0 | 25.7 |
| Multiple waterways | 44.0 | 0.4 | 42.7 | 0.4 | 43.8 | 2.3 | S |
| Air (includes truck and air) | 12.8 | Z | 29.3 | Z | 38.4 | Z | 8.7 |
| Pipeline (3) | 9.3 | 2.0 | 11.0 | 2.3 | S | S | S |
| Multiple modes | 15.6 | 0.2 | 30.9 | 0.3 | 45.8 | 3.4 | 6.2 |
| Parcel, U.S. Postal Service, or courier | 11.0 | 0.1 | 9.0 | Z | 10.4 | Z | 6.2 |
| Truck and rail | 14.5 | 0.1 | 15.6 | 0.1 | 14.0 | 0.8 | 9.2 |
| Truck and water | S | S | S | S | S | S | 14.1 |
| Rail and water | 30.6 | Z | 42.5 | 0.1 | 33.3 | 0.2 | S |
| Other multiple modes | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Other modes | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
KEY: S = Withheld because estimate did not meet publication standards.
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/econ/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.