Table B-2. Estimated Measures of Reliability for Shipment Characteristics by Total Modal Activity for State of Origin: 2002
Monday, July 2, 2012
Table B-2. Estimated Measures of Reliability for Shipment Characteristics by Total Modal Activity for State of Origin: 2002
[Estimates are based on data from the Commodity Flow Survey. Because of rounding, estimates may not be additive]
| Mode of transportation | Ton-miles | CV of average miles per shipment |
|
|---|---|---|---|
| CV | Std. error of percent | ||
| Total | 9.4 | – | 7.7 |
| Truck | 10.3 | 4.4 | 7.8 |
| Rail | 16.3 | 2.3 | 8.2 |
| Shallow draft | – | – | – |
| Great Lakes | 29.4 | 3.0 | 15.1 |
| Deep draft | S | S | S |
| Air | 31.0 | – | 5.0 |
| Parcel, USPS or courier | 30.7 | 0.1 | 26.5 |
| Pipeline | S | S | S |
| Other and unknown modes | 31.3 | 0.5 | 41.2 |
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.
CV Coefficient of variation of number
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, Individual State Data, December 2004.