Notes: All data-Trade levels reflect the mode of transportation as a shipment enters or exits a U.S. Customs port. Flows through individual ports are based on reported data collected from U.S. trade documents. Low-value shipments (imports less that $1,250 and exports less than $2,500) and intransit shipments are not included in trade data. Air-Data for all airports are based on U.S. port classifications and include a low level (generally less than 2% to 3% of the total value) of small user-fee airports located in the same region. Air gateways not identified by airport name include major airports in that geographic area in addition to small regional airports. Also due to U.S. Census Bureau confidentiality regulations, data for some of the air gateways include courier operations. For example, data for New Orleans Custom Port's international air cargo include FedEx air cargo activity in Memphis, TN.
SOURCES: Air-U.S. Department of Commerce, U.S. Census Bureau, Foreign Trade Division, special tabulation, August 2004. Water-U.S. Department of Transportation, Maritime Administration, Office of Statistical and Economic Analysis, special tabulations from Waterborne Databank, August 2004. Land-U.S. Department of Transportation, Bureau of Transportation Statistics, Transborder Surface Freight Data as of August 2004. U.S. Department of Transportation, Bureau of Transportation Statistics, based on data from U.S. Department of Homeland Security, Customs and Border Protection, Operations Management Database, 1994-2003.