Estimates are based on preliminary data from the 2007 Commodity Flow Survey. Because of rounding, estimates may not be additive
|Mode of transportation (1)||2007
|2007 Average miles per shipment||Ton-miles CV (3)||Average miles per shipment CV|
|Air (included truck and air)||4,166||1,154||15.4||2.2|
|Parcel, U.S.P.S. or courier||29,426||911||3.1||1.5|
|Other and unknown modes||41,271||103||7.9||11.0|
S Estimate does not meet publication standards because of high sampling variability or poor response quality.
(1) Estimates represent activity for a given mode across single and multiple mode shipments. For example, "Truck" ton-miles includes total ton-miles for shipments moving only by truck plus ton-miles for truck segments of multiple mode shipments.
(2) Ton-miles estimates are based on estimated distances traveled along a modeled transportation network.
(3) Coefficient of Variation.
(4) Estimates exclude shipments of crude petroleum.
NOTE: These data are preliminary
and are subject to change; they will be superseded by data released in later
reports. Value-of-shipment estimates have not been adjusted for price
changes. Estimated measures of sampling variability for each estimate known
as coefficients of variation (CV) are also provided in these tables.
More information on sampling error, confidentiality protection, nonsampling error, sample design, and definitions may be found at http://www.census.gov/cfs.
SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics and U.S. Department of Commerce, U.S. Census Bureau, 2007 Economic Census: Transportation Commodity Flow Survey, Preliminary Release, December 2008.