Table B-17. Estimated Measures of Reliability for Shipment Characteristics of Temperature Controlled Shipments (1) by Total Modal Activity for the United States: 2012
(Estimates are based on data from the 2012 Commodity Flow Survey)
| Mode of transportation (2) | Ton-miles (3) | Average miles per shipment | |
|---|---|---|---|
| Coefficient of variation of number | Standard error of percent of total | coefficient of variation of number | |
| Total | 2.1 | 0 | 5.8 |
| Truck (4) | 2.5 | 1.3 | 4.6 |
| Rail | 6.5 | 0.9 | 13.2 |
| Inland water | 43.7 | 0.7 | 35.1 |
| Great Lakes | S | S | 36.3 |
| Deep sea | 17.3 | 0.2 | 13.1 |
| Air (includes truck and air) | S | S | 13.3 |
| Pipeline (5) | S | S | S |
| Parcel, U.S. Postal Service, or courier | 16.9 | Z | 6.8 |
| Other modes | 0 | 0 | 0 |
KEY: S = Withheld because estimate did not meet publication standards.
Z = Rounds to zero.
(1) Shipments that are temperature controlled are transported in a vehicle or container that regulates or maintains the temperature when en route to its destination.
(2) Estimates represent activity for a given mode across single and multiple mode shipments. For example, “Truck” ton-miles includes total ton-miles for shipments moving only by truck plus ton-miles for truck segments of multiple mode shipments.
(3) Ton-miles estimates are based on estimated distances traveled along a modeled transportation network. See “Mileage Calculations” section for additional information.
(4) “Truck” as a single mode includes shipments that were made by only private truck or only for-hire truck.
(5) 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.