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 | 39.2 | – | 15.7 |
| Truck | 12.5 | 6.7 | 24.2 |
| Rail | S | S | 4.1 |
| Shallow draft | 19.1 | 4.2 | 11.1 |
| Great Lakes | – | – | – |
| Deep draft | – | – | – |
| Air | S | S | 8.4 |
| Parcel, USPS or courier | S | S | 31.4 |
| Pipeline | S | S | S |
| Other and unknown modes | S | S | S |
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.