"Table 1-52:  U.S. Hazardous Materials Shipments by Mode of Transportation, 1997",,,,,,,,
,Value,,Tons,,Ton-miles,,,
Mode of Transportation,($ million),Percent,(thousands),Percent,(millions),Percent,,
Single modes,452.7,97.1,"1,541.7",98.5,258.9,98.1,,
Trucka,298.2,63.9,869.8,55.6,74.9,28.4,,
  For-hire,134.3,28.8,336.4,21.5,45.2,17.1,,
  Privateb,160.7,34.5,522.7,33.4,28.8,10.9,,
Rail,33.3,7.1,96.6,6.2,74.7,28.3,,
Water,27.0,5.8,143.2,9.1,68.2,25.9,,
Air,8.6,1.8,0.1,–,0.1,–,,
Pipelinec,85.7,18.4,432.1,27.6,S,S,,
,,,,,,,,
Multiple modes,5.7,1.2,6.0,0.4,3.1,1.2,,
"Parcel, U.S. Postal Service or Courier",2.9,0.6,0.1,–,0.1,–,,
Other,2.9,0.6,5.9,0.4,3.0,1.1,,
,,,,,,,,
Unknown and other modes,7.9,1.7,17.5,1.1,1.8,0.7
,,,,,,
All modes,466.4,100.0,"1,565.2",100.0,263.8,100.0
KEY:  – = less than 1 unit of measure or equal to zero; S = data are not published because of high sampling variability or other reasons. ,,,,,,
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"a Truck as a single mode includes shipments that went by private truck only, for-hire truck only, or a combination of both.",,,,,,
b Private truck refers to a truck operated by a temporary or permanent employee of an establishment or the buyer/receiver of the shipment.,,,,,,
c Excludes most shipments of crude oil.  See previous table for the estimated amount of crude oil and petroleum products transported in the United States.,,,,,,
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NOTE:  Numbers and percents may not add to totals due to rounding.,,,,,,
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"SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics,  U.S. Department of Commerce, Census Bureau, 1997 Economic Census 1997 Commodity Flow Survey, Hazardous Materials (Washington, DC: December 1999), table 1.",,,,,,
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