Sustainable Worldwide

Eco-Driving Index

The sales-weighted unadjusted Corporate Average Fuel Economy (CAFE) performance was calculated from the monthly sales of individual models of light-duty vehicles and the unadjusted combined city/highway fuel-economy ratings for the respective models. (Datafiles containing summaries of test-level data for individual models, including unadjusted fuel-economy ratings, are available for download from the EPA for each model year.) For both monthly and model year averages, sales-weighted harmonic means were calculated. The bars in the graph show the average for each model year. Vehicles purchased from October 2007 through September 2008 were assumed to be model year 2008. Analogous assumptions were made for vehicles purchased in each following model year. The unadjusted fuel-economy information was available for 99.8% of vehicles purchased.

These unadjusted fuel-economy ratings are not directly comparable to the "window sticker" ratings published in the EPA Fuel Economy Guide. These raw values are adjusted by the EPA to derive the estimated on-road fuel-economy ratings that are published in the EPA guide and on window stickers.

For cases in which the EPA datafile contained multiple unadjusted fuel-economy ratings for a vehicle model, the average of these ratings was used (without regard to sales figures for each specific engine or vehicle-model variant). Additionally, when a vehicle model was sold during a particular model year but it is not listed in that year’s EPA data file, the fuel-economy rating(s) from the most recently available year were used. Finally, for very low sales-volume manufacturers (e.g., Ferrari, Rolls-Royce, etc.), all vehicle models for that manufacturer were aggregated and one average unadjusted fuel-economy rating was calculated. Analogously, the sales figures for such manufacturers and models were also aggregated each month. (Data for recent months are occasionally updated in the underlying EPA data source, possibly resulting in small changes to recent fuel economy values.)

Note: These calculations do not take into account the various credits and adjustments available to manufacturers when determining final CAFE performance values. Consequently, these values cannot be used for assessing compliance with CAFE standards because the results may underestimate the final CAFE values.

Latest data: June 2014.

Last updated: July 2, 2014.

This update includes the corrections in the EPA ratings for the Ford vehicles that were issued on June 11, 2014.


(click on the graph to view full size)

Sales-weighted CAFE graph


Download the current sales-weighted unadjusted CAFE data

Year Month
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
2007                   24.7 25.0 24.8
2008 25.2 25.1 25.6 25.9 26.7 26.4 26.1 25.6 25.3 25.7 25.4 25.3
2009 25.9 26.0 26.2 26.2 26.3 26.4 27.2 27.7 25.9 27.4 27.4 27.3
2010 27.6 27.5 27.6 27.5 27.5 27.3 27.4 27.4 27.2 27.7 27.7 27.7
2011 28.0 28.2 28.6 28.5 28.2 27.9 27.9 27.3 27.5 28.4 28.4 27.6
2012 29.0 29.3 29.5 29.3 29.1 29.0 29.0 29.2 29.2 29.5 29.6 29.2
2013 29.8 29.8 30.0 29.9 29.9 29.9 29.9 30.1 29.7 30.4 30.5 30.3
2014 30.3 30.8 31.0 30.7 31.1 31.0            


Page updated: Wednesday, July 2, 2014

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