Table B-4b. Estimated Measures of Reliability for Shipment Characteristics by Shipment Weight for the United States: 2012 and 2007
(Estimates are based on data from the 2012 and 2007 Commodity Flow Surveys)
Shipment weight | Value | Tons | Ton-miles (1) | Average miles per shipment | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Coefficient of variation of number | Standard error of percent change | Coefficient of variation of number | Standard error of percent change | Coefficient of variation of number | Standard error of percent change | Coefficient of variation of number | Standard error of percent change | |||||
2012 | 2007 | 2012 | 2007 | 2012 | 2007 | 2012 | 2007 | |||||
Total | 1.1 | 0.8 | 1.6 | 1.8 | 1.6 | 2.2 | 3.7 | 3.6 | 4.5 | 3.4 | 2.5 | 4.3 |
Less than 50 lbs. | 1.5 | 1.9 | 3.1 | 4.0 | 2.1 | 5.7 | 4.0 | 3.4 | 6.3 | 3.4 | 2.6 | 4.1 |
50 to 99 lbs. | 2.8 | 2.6 | 4.5 | 2.3 | 2.0 | 3.2 | 2.7 | 3.9 | 4.8 | 2.4 | 3.0 | 3.6 |
100 to 499 lbs. | 1.7 | 1.9 | 2.7 | 1.7 | 1.4 | 2.2 | 2.5 | 3.4 | 4.3 | 2.3 | 2.7 | 3.6 |
500 to 749 lbs. | 2.3 | 1.9 | 3.5 | 1.7 | 1.3 | 2.2 | 2.1 | 2.4 | 3.3 | 1.9 | 2.6 | 3.3 |
750 to 999 lbs. | 3.5 | 3.1 | 5.3 | 2.3 | 1.7 | 2.9 | 2.6 | 5.5 | 5.7 | 1.9 | 4.8 | 5.0 |
1,000 to 9,999 lbs. | 1.7 | 1.8 | 2.7 | 2.3 | 1.1 | 2.5 | 2.0 | 1.7 | 2.5 | 1.8 | 1.7 | 2.4 |
10,000 to 49,999 lbs. | 1.3 | 1.8 | 2.6 | 1.6 | 1.8 | 2.1 | 1.9 | 1.2 | 2.0 | 1.7 | 1.5 | 2.4 |
50,000 to 99,999 lbs. | 4.3 | 3.3 | 8.4 | 2.9 | 2.2 | 3.5 | 3.3 | 3.1 | 3.8 | 2.5 | 3.0 | 3.5 |
100,000 lbs. or more | 4.4 | 4.4 | 8.5 | 4.5 | 3.3 | 5.1 | 6.1 | 5.9 | 7.4 | 3.1 | 2.9 | 4.1 |
(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.