Table B-1a. Estimated Measures of Reliability for Hazardous Material Shipment Characteristics by Mode of Transportation: 2002
Monday, July 2, 2012
Table B-1a. Estimated Measures of Reliability for Hazardous Material Shipment Characteristics by Mode of Transportation: 2002
[Estimates are shown as percents and are based on data from the 2002 Commodity Flow Survey]
| Mode of transportation | Value | Tons | Ton-miles | CV of average miles per shipment |
|||
|---|---|---|---|---|---|---|---|
| CV | Std. error of percent | CV | Std. error of percent | CV | Std. error of percent | ||
| All modes | 3.0 | – | 4.2 | – | 4.4 | – | 7.1 |
| Single modes | 3.1 | 0.2 | 4.2 | 0.2 | 4.9 | 0.9 | 6.1 |
| Truck | 3.7 | 1.4 | 4.6 | 1.3 | 7.0 | 2.0 | 6.3 |
| For-hire truck | 5.2 | 1.2 | 6.2 | 0.8 | 9.4 | 1.8 | 7.4 |
| Private truck | 4.8 | 1.3 | 5.3 | 1.3 | 7.9 | 1.1 | 5.3 |
| Rail | 7.7 | 0.4 | 6.6 | 0.3 | 5.8 | 1.6 | 2.6 |
| Water | 12.5 | 0.8 | 14.3 | 1.3 | 12.0 | 2.2 | S |
| Air (includes truck and air) | 20.7 | – | 38.0 | – | 39.2 | – | 8.2 |
| Pipeline | 6.6 | 1.2 | 7.0 | 1.4 | S | S | S |
| Multiple modes | 14.9 | 0.2 | 24.3 | 0.2 | 19.9 | 0.9 | 12.8 |
| Parcel, U.S.P.S. or courier | 14.6 | 0.1 | 20.2 | – | 13.0 | – | 13.2 |
| Other multiple modes | 23.6 | 0.2 | 24.7 | 0.2 | 20.1 | 0.9 | 22.6 |
| Other and unknown modes | 18.7 | 0.2 | 19.0 | 0.1 | 46.0 | 0.4 | 39.0 |
KEY:
– Represents and estimate equal to
zero or less than 1 unit of measure.
S Estimate does not meet publication standards b ecause of highly sampling
variability or poor response quality.
CV Coefficient of variation of number
NOTE: 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, Hazmat Data, December 2004.