|Number registered (thousands)||3,681||4,232||4,374||4,593||4,487||4,481||4,370||4,408||4,906||5,024||5,266||5,293||5,735||5,763||5,926||5,704||5,651||5,849||6,161||6,395||6,649||8,117||8,288||8,356||8,217||7,819||8,190||8,126|
|Fuel consumed (million gallons)||3,968||5,420||6,923||7,399||8,357||8,172||8,237||8,488||9,032||9,216||9,409||9,576||9,741||9,372||9,563||9,667||10,321||8,880||8,959||9,501||9,852||16,314||17,144||16,253||15,097||14,215||14,376||14,502|
|Average miles traveled per vehicle (thousands)||7.4||8.2||9.1||9.9||11.6||11.8||12.3||12.9||12.5||12.5||12.2||12.6||11.9||12.2||11.9||12.7||13.4||13.3||12.7||12.3||12.1||14.8||15.3||14.4||13.5||13.3||12.9||13.1|
|Average miles traveled per gallon||6.8||6.4||5.7||6.1||6.2||6.5||6.5||6.7||6.8||6.8||6.8||7.0||7.0||7.5||7.4||7.5||7.4||8.8||8.8||8.3||8.2||7.4||7.4||7.4||7.3||7.3||7.3||7.3|
|Average fuel consumed per vehicle (gallons)||1,077.8||1,280.8||1,582.8||1,610.9||1,862.5||1,823.8||1,885.0||1,925.7||1,840.9||1,834.5||1,786.7||1,809.1||1,698.5||1,626.3||1,613.7||1,695.0||1,826.5||1,518.4||1,454.1||1,485.6||1,481.7||2,010.0||2,068.5||1,945.0||1,837.2||1,818.0||1,755.3||1,784.6|
KEY: R = revised.
a Beginning in 1998, the Federal Highway Administration (FHWA) used the Census Bureau's 1997 Vehicle Inventory and Use Survey (VIUS) for its baseline estimate of single-unit 2-axle 6-tire or more trucks. Prior to 1998, the FHWA used the Census Bureau's 1992 Transportation Inventory and Use Survey (TIUS) for its baseline estimates. Therefore, post-1997 data may not be comparable to 1997 and earlier years.
Data for 2007-13 were calculated using new sources and a new methodology developed by FHWA. Data for these years are not comparable to previous years. The FHWA estimates national trends by using State reported Highway Performance and Monitoring System (HPMS) data, fuel consumption data (MF-21 and MF-27), vehicle registration data (MV-1, MV-9, and MV-10), other data such as the R. L. Polk vehicle data, and a host of modeling techniques. Starting with the 2007 VM-1, an enhanced methodology is used to provide timely indictors on both travel and travel behavior changes.
From 1998-2006, the Federal Highway Administration (FHWA) used the Census Bureau's Vehicle Inventory and Use Survey (VIUS) for its baseline estimate of single-unit 2-axle 6-tire or more trucks. Prior to 1998, the FHWA used the Census Bureau's 1992 Transportation Inventory and Use Survey (TIUS) for its baseline estimates. Therefore, post-1997 data may not be comparable to 1997 and earlier years.
In 1995, the U.S. Department of Transportation, Federal Highway Administration revised its vehicle categories beginning with 1993 data to include passenger cars, other 2-axle 4-tire vehicles, single-unit 2-axle 6-tire or more trucks, and combination trucks. Single-Unit 2-Axle 6-tire or More trucks are those that have single frames, two axles, and at least 6 tires or a gross vehicle weight rating exceeding 10,000 lbs.. Pre-1993 data have been reassigned to the most appropriate category.
1970-94: U.S. Department of Transportation, Federal Highway Administration, Highway Statistics Summary to 1995, FHWA-PL-97-009 (Washington, DC: July 1997), table VM-201A, available at http://www.fhwa.dot.gov/policy/ohpi/hss/hsspubs.cfm as of Mar. 23, 2009.
1995-2013: Ibid., Highway Statistics (Washington, DC: Annual issues), table VM-1, available at http://www.fhwa.dot.gov/policyinformation/statistics.cfm as of June 25, 2015.