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Table B–2e. Estimated Standard Errors for Shipment Characteristics by Total Modal Activity for the United States: Percent of Total for 2002, 1997, and 1993
[Estimates are shown as percents and are based on data from the 2002, 1997, and 1993 Commodity Flow Surveys]
Excel | CSV
| Total |
– |
– |
– |
| Truck |
1.5 |
1.1 |
0.9 |
| Rail |
1.6 |
1.5 |
0.9 |
| Shallow draft |
0.6 |
0.4 |
1.0 |
| Great Lakes |
0.3 |
0.2 |
0.3 |
| Deep draft |
0.4 |
0.5 |
0.5 |
| Air |
– |
– |
– |
| Parcel, U.S.P.S. or
courier |
– |
– |
– |
| Pipeline |
S |
S |
S |
| Other and unknown modes |
0.2 |
0.3 |
0.5 |
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.
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: Bureau of Transportation Statistics (USDOT) and U.S. Census Bureau, 2002 Commodity Flow Survey, United States Data, December 2004.
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