Table B-4b. Estimated Measures of Reliability for Shipment Characteristics by Shipment Weight: 2002 and 1997
Monday, July 2, 2012
Table B-4b. Estimated Measures of Reliability for Shipment Characteristics by Shipment Weight: 2002 and 1997
[Estimates are shown as percents and are based on data from the 2002 and 1997 Commodity Flow Surveys]
| Shipment Weight | Value Coefficient of variation of number |
Value Standard error of percent |
Tons Coefficient of variation of number |
Tons Standard error of percent |
Ton-Miles Coefficient of variation of number |
Ton-Miles Standard error of percent |
Average miles per shipment Coefficient of variation of number |
Average miles per shipment Standard error of percent |
||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2002 | 1997 | 2002 | 1997 | 2002 | 1997 | 2002 | 1997 | |||||
| All shipment sizes | 1.3 | 0.9 | 2.0 | 2.0 | 1.6 | 2.8 | 3.7 | 2.3 | 5.3 | 2.9 | 2.6 | 4.4 |
| Less than 50 lbs | 2.5 | 1.9 | 3.7 | 2.7 | 2.5 | 3.6 | 3.5 | 3.7 | 5.4 | 2.8 | 2.9 | 4.7 |
| 50 to 99 lbs | 5.6 | 2.1 | 7.2 | 4.7 | 2.0 | 5.6 | 6.8 | 4.2 | 9.4 | 5.4 | 3.4 | 7.0 |
| 100 to 499 lbs | 3.0 | 2.3 | 4.3 | 3.4 | 1.3 | 4.0 | 2.6 | 3.1 | 4.6 | 3.5 | 3.0 | 4.9 |
| 500 to 749 lbs | 3.3 | 2.1 | 4.4 | 3.3 | 1.3 | 3.8 | 2.8 | 4.8 | 6.1 | 3.3 | 3.8 | 5.1 |
| 750 to 999 lbs | 3.8 | 3.2 | 6.0 | 4.6 | 1.7 | 5.5 | 2.6 | 6.4 | 7.5 | 4.4 | 5.2 | 6.5 |
| 1,000 to 9,999 lbs | 2.6 | 2.4 | 4.2 | 1.9 | 1.5 | 2.7 | 3.7 | 3.4 | 6.0 | 2.8 | 3.1 | 4.5 |
| 10,000 to 49,999 lbs | 1.7 | 1.7 | 3.3 | 3.3 | 1.9 | 4.2 | 2.1 | 1.9 | 3.4 | 2.7 | 1.6 | 3.4 |
| 50,000 to 99,999 lbs | 3.6 | 3.7 | 5.7 | 3.8 | 2.9 | 5.2 | 4.6 | 2.7 | 5.8 | 4.5 | 2.5 | 5.3 |
| 100,000 lbs or more | 6.5 | 3.9 | 8.5 | 3.4 | 3.5 | 5.4 | 6.2 | 4.1 | 9.1 | 3.2 | 4.9 | 6.5 |
KEY:
– Represents data cell equal to zero or less than 1 unit of measure.
S Estimate does not meet publication standards because of high sampling variability or poor response quality.
NOTE: The Introduction and appendixes give information onf 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: Bureau of Transportation Statistics (USDOT) and U.S. Census Bureau, 2002 Commodity Flow Survey, United States Data, December 2004.