Table B-2a. Estimated Measures of Reliability for Export Shipment Characteristics by Domestic Mode: 2002
[Estimates are shown as percents and are based on data from the 2002 Commodity Flow Survey]
|Domestic mode of transportation||Value||Tons||Ton-miles|
|CV 02||Std. error of percent||CV 02||Std. error of percent||CV 02||Std. error of percent|
|Air (including truck and air)||9.9||1.0||24.1||–||31.5||0.3|
|Parcel, U.S.P.S. or courier||8.1||0.8||7.8||–||14.4||–|
|Truck and rail||10.4||0.3||15.8||0.6||6.4||0.7|
|All other multiple modes||28.9||–||26.3||0.3||38.4||1.3|
|Other and unknown modes||16.4||0.4||21.1||0.3||22.2||0.2|
– Represents an estimate 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 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: Research and Innovative Technologies Administration, Bureau of Transportation Statistics (USDOT) and U.S. Census Bureau, 2002 Commodity Flow Survey, Export Data, March 2005.