|Millions of tons||Billions of 2007 U.S. Dollars||Millions of tons||Billions of 2007 U.S. Dollars||Millions of tons||Billions of 2007 U.S. Dollars|
|All modes, total||18,879||16,651||17,622||16,804||28,520||39,265|
|Air, air & truck||13||1,077||17||1,219||53||5,043|
|Multiple modes & mail||1,415||2,877||1,618||3,099||3,575||9,925|
|Other & unknown||316||341||313||341||526||821|
NOTES: Numbers may not add to total due to rounding. The 2011 data are provisional estimates, which are based on selected modal and economic trend data. All truck, rail, water, and pipeline movements that involve more than one mode, including exports and imports that change mode at international gateways, are included in multiple modes & mail to avoid double counting. As a consequnce, rail and water totals in this table are less than those reported in other sources.
SOURCE: U.S. Department of Transportation, Federal Highway Administration, Office of Freight Management and Operations, Freight Analysis Framework, version 3.4, 2012.