US Table B–2a,,,,
"Estimated Measures of Reliability for Shipment Characteristics by Total Modal Activity for the United States: 2002
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"[Estimates are shown as percents and are based on data from the 2002 Commodity Flow Survey]
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Mode of transportation,"
Ton–miles",,CV of Average miles per shipment ,
,CV ,Std. error of  percent,,
Total,3.7,—,2.8,
Truck,2.8,1.5,3.6,
Rail,7.6,1.6,6.1,
Shallow draft,9.4,0.6,13.1,
Great Lakes,18.1,0.3,16.0,
Deep draft,17.3,0.4,11.1,
Air,15.7,—,4.3,
"Parcel, U.S.P.S. or courier",4.2,—,2.3,
Pipeline,S,S,S,
Other and unknown modes,9.7,0.2,13.0,
"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 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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