Table B-4. Estimated Measures of Reliability for Hazardous Versus Nonhazardous Material Shipment Characteristics by Mode of Transportation: 2002
Table B-4. Estimated Measures of Reliability for Hazardous Versus Nonhazardous 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 | Tons - CV | Tons - Hazardous | Tons - Nonhazardous | Ton-miles - CV | Ton-miles - Hazardous | Ton-miles - Nonhazardous | ||||
---|---|---|---|---|---|---|---|---|---|---|
CV | Std. error of percent | CV | Std. error of percent | CV | Std. error of percent | CV | Std. error of percent | |||
All modes | 1.1 | 4.2 | 0.7 | 1.3 | 0.7 | 3.2 | 4.4 | 0.5 | 3.4 | 0.5 |
Single modes | 1.4 | 4.2 | 0.7 | 1.5 | 0.7 | 3.0 | 4.9 | 0.5 | 3.2 | 0.5 |
Truck | 1.9 | 4.6 | 0.7 | 2.2 | 0.7 | 3.2 | 7.0 | 0.5 | 3.1 | 0.5 |
For– hire truck | 3.8 | 6.2 | 0.7 | 4.2 | 0.7 | 3.6 | 9.4 | 0.6 | 3.5 | 0.6 |
Private truck | 2.3 | 5.3 | 0.7 | 2.2 | 0.7 | 3.9 | 7.9 | 0.8 | 3.6 | 0.8 |
Rail | 3.3 | 6.6 | 0.4 | 3.4 | 0.4 | 6.6 | 5.8 | 0.4 | 6.9 | 0.4 |
Water | 8.5 | 14.3 | 3.2 | 8.7 | 3.2 | 8.0 | 12.0 | 3.0 | 10.1 | 3.0 |
Air (includes truck and air) | 12.7 | 38.0 | 0.5 | 12.5 | 0.5 | 17.4 | 39.2 | 0.5 | 17.3 | 0.5 |
Pipeline | 6.8 | 7.0 | 0.5 | 15.0 | 0.5 | S | S | S | S | S |
Multiple modes | 8.1 | 24.3 | 1.8 | 8.5 | 1.8 | 13.6 | 19.9 | 1.3 | 14.9 | 1.3 |
Parcel, U.S.P.S. or courier | 4.8 | 20.2 | 0.2 | 4.9 | 0.2 | 4.9 | 13.0 | – | 4.9 | – |
Other multiple modes | 9.3 | 24.7 | 2.1 | 10.0 | 2.1 | 14.9 | 20.1 | 1.5 | 16.4 | 1.5 |
Other and unknown modes | 12.9 | 19.0 | 1.1 | 13.4 | 1.1 | 10.5 | 46.0 | 1.7 | 9.8 | 1.7 |
KEY:
– Represents an estimate equal to zero or less than 1 unit of measure.
S Estimate does not meet publication standards because 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.