US Table B—4b,,,,,,,,,,,, "Estimated Measures of Reliability for Shipment Characteristics by Shipment Weight: 2002 and 1997 ",,,,,,,,,,,, "[Estimates are shown as percents and are based on data from the 2002 and 1997 Commodity Flow Surveys] ",,,,,,,,,,,, Shipment Weight,Value,,,Tons,,,Ton—Miles,,,Average miles per shipment,, ,Coefficient of variation of number,,Standard error of percent,Coefficient of variation of number,,Standard error of percent,Coefficient of variation of number,,Standard error of percent,Coefficient of variation of number,,Standard error of percent ,2002,1997,,2002,1997,,2002,1997,,2002,1997, All shipment sizes,1.3,0.9,2.0,2.0,1.6,2.8,3.7,2.3,5.3,2.9,2.6,4.4 Less than 50 lbs,2.5,1.9,3.7,2.7,2.5,3.6,3.5,3.7,5.4,2.8,2.9,4.7 50 to 99 lbs,5.6,2.1,7.2,4.7,2.0,5.6,6.8,4.2,9.4,5.4,3.4,7.0 100 to 499 lbs,3.0,2.3,4.3,3.4,1.3,4.0,2.6,3.1,4.6,3.5,3.0,4.9 500 to 749 lbs,3.3,2.1,4.4,3.3,1.3,3.8,2.8,4.8,6.1,3.3,3.8,5.1 750 to 999 lbs,3.8,3.2,6.0,4.6,1.7,5.5,2.6,6.4,7.5,4.4,5.2,6.5 "1,000 to 9,999 lbs",2.6,2.4,4.2,1.9,1.5,2.7,3.7,3.4,6.0,2.8,3.1,4.5 "10,000 to 49,999 lbs",1.7,1.7,3.3,3.3,1.9,4.2,2.1,1.9,3.4,2.7,1.6,3.4 "50,000 to 99,999 lbs",3.6,3.7,5.7,3.8,2.9,5.2,4.6,2.7,5.8,4.5,2.5,5.3 "100,000 lbs or more",6.5,3.9,8.5,3.4,3.5,5.4,6.2,4.1,9.1,3.2,4.9,6.5 "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.",,,,,,,,,,,, "NOTE: The Introduction and appendixes give information onf 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.",,,,,,,,,,,,