Table B-4a. Estimated Measures of Reliability for Shipment Characteristics by Shipment Weight for the United States: 2012
Monday, July 13, 2015
(Estimates are based on data from the 2012 Commodity Flow Survey)
| 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 | ||
| Total | 1.1 | 0.0 | 1.8 | 0.0 | 3.7 | 0.0 | 3.4 |
| Less than 50 lbs. | 1.5 | 0.2 | 4.0 | Z | 4.0 | Z | 3.4 |
| 50 to 99 lbs. | 2.8 | 0.1 | 2.3 | Z | 2.7 | Z | 2.4 |
| 100 to 499 lbs. | 1.7 | 0.2 | 1.7 | Z | 2.5 | Z | 2.3 |
| 500 to 749 lbs. | 2.3 | 0.1 | 1.7 | Z | 2.1 | Z | 1.9 |
| 750 to 999 lbs. | 3.5 | 0.1 | 2.3 | Z | 2.6 | Z | 1.9 |
| 1,000 to 9,999 lbs. | 1.7 | 0.3 | 2.3 | 0.2 | 2.0 | 0.2 | 1.8 |
| 10,000 to 49,999 lbs. | 1.3 | 0.3 | 1.6 | 0.6 | 1.9 | 1.1 | 1.7 |
| 50,000 to 99,999 lbs. | 4.3 | 0.3 | 2.9 | 0.5 | 3.3 | 0.2 | 2.5 |
| 100,000 lbs. or more | 4.4 | 0.4 | 4.5 | 1.0 | 6.1 | 1.4 | 3.1 |
KEY: 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.
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.