Trends Away From Efficiency

Blog Post | January 01, 2007 - 12:00 am

A simple equation can help explain America's increasing use and dependence on oil: (stagnating fuel economy) * (increasing miles traveled) = (rising petroleum use).
 

Fuel Economy Improvements Have Leveled Off

Source: EPA's Light-Duty Automotive Technology and Fuel Economy Trends 1975 Through 2005
 

Despite technological improvements, overall fuel economy has stagnated. This is largely because automakers have eschewed fuel economy for power improvements, especially in the immensely popular pickup truck and SUV market segments.
 

Americans Keep Driving More

Source: FHA's Highway Statistics Table VM-1 (passenger cars plus single-unit 2-axle 4-tire trucks)
 

The increase in population over the same time span does not nearly account for the rapid increase in miles driven. Between 1970 and 2000, population increased by 38.4% while vehicle miles travelled rose by 142.6%

Year
Population
Percent Increase From Previous Decade
Millions of Vehicle Miles Driven
Percentage Increase From Previous Decade
1970
203,302,031
 
1,039,986
 
1980
226,542,199
11.4%
1,402,531
34.9%
1990
248,709,873
9.8%
1,979,276
41.1%
2000
281,421,906
13.2%
2,523,346
27.5%