Box D - Interpreting Value, Tons, and Ton-Miles in the Commodity Flow Survey

Value of shipments. The CFS defines the value of shipments as the market value in dollars of goods shipped by businesses. It represents the net selling value, excluding freight charges and taxes. CFS measures the value of shipments of materials used to produce or manufacture a product and the value of shipments of the finished product. This means that the value of the intermediate materials used to produce a particular product could contribute multiple times to the value if it is shipped multiple times during the survey year. For example, if a $1,000 product is shipped from a manufacturer in Boston, MA to a distributor in Washington, DC, who ships it to a wholesaler in Chicago, IL, who then ships it to a retail outlet in Los Angeles, CA, the value of the shipment (product) is counted three times if the manufacturer, distributor, and wholesaler are sampled by the CFS. Each shipment is counted to represent each transportation movement (solid lines in the map). The same product is counted only once, however, if it is directly shipped from the manufacturer in Boston to the retailer in Los Angeles (dotted line in the map).

Tonnage of shipments. This represents the total weight of a shipment. Businesses report the entire weight of a shipment in pounds. As with value of shipments above, the tonnage of a product could be counted multiple times depending on the number of times the product is transported in the production and consumption cycle.

Ton-miles. Ton-miles measure the shipment weight multiplied by the mileage traveled by the shipment. Businesses report shipment weight in pounds. Aggregated pound-miles were converted to ton-miles. Mileage is calculated as the distance between the shipment origin and destination ZIP Codes. For all shipments, the CFS mileage excludes the international portion of the distance, starting from the final U.S. port of exit. For example, mileages from Alaska to the continental United States exclude any mileages through Canada . And air shipments from Denver, Colorado to Japan exclude the mileage over U.S. airspace from the airport in Denver. Unlike value and tonnage, the CFS total for ton-miles is not subject to multiple counting because the number of times goods are shipped does not affect the calculations.

For additional information, visit http://www.bts.gov/cfs.

SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics based on Bureau of Transportation Statistics and U.S. Department of Commerce, Census Bureau, 2002 Economic Census: Transportation 2002 Commodity Flow Survey, United States 2002. December 2004; and examples from the Bureau of Transportation Statistics.