Fuel Economy Leadership Issue Brief

Marcos Frommer There are few calculations more confusing in the auto industry than the statistical ratings used by the government to measure and report...

Marcos Frommer

There are few calculations more confusing in the auto industry than the statistical ratings used by the government to measure and report on automobile fuel economy. There are adjusted and unadjusted numbers, label values, CAFE (Corporate Average Fuel Economy) ratings, CO2 emissions data and more. These are then re-positioned by various carmakers to claim bragging rights as the most "fuel efficient" car company in America. You've got a recipe for confusion and, potentially, for the misreporting of the facts.

So let's stick to the facts. The U.S. EPA recently released its annual report on fuel economy trends: "Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 - 2009," Executive Summary, page VII (November, 2009) Here's what the EPA says:

  • "In MY [Model Year] 2008, the last year for which EPA has essentially complete formal production data, [American] Honda had the lowest fleetwide adjusted composite CO2 emissions (and highest fuel economy) performance ..." (This includes both Honda and Acura vehicles.)

This is all very clear. No footnotes. No fine print.

The EPA also recently released "preliminary" data for Model Year 2009. So, why not use MY 2009 numbers? Because the EPA bases its final judgment of fuel economy leadership for any given year on the complete year-end results, and 2009 complete data won't be available until next year. The EPA has stated that it cannot adequately judge fuel economy leadership on preliminary data:

  • "EPA has less confidence in the MY2009 data as it is based on automaker projections of production volumes submitted to EPA prior to the start of the 2009 model year. EPA anticipates this data will change for all automakers after the final MY2009 data has been submitted to EPA . . . ." [p. 27].
  • "It is impossible to predict whether actual MY2009 fuel efficiency data will be higher or lower than the preliminary MY2009 value." [p. ii];

So, the EPA has made it abundantly clear that it makes little sense for any automaker to determine a fuel economy claim on preliminary data. We agree. And even though EPA says "preliminary MY2009 values suggest that [American] Honda will continue to have the lowest fleetwide CO2 emissions (and highest fuel economy)," we'll wait until EPA provides complete data for 2009.

But let's provide a little additional context.

Looking back: the EPA's very first ranking of America's most fuel efficient vehicles in 1976, had the Honda Civic ranked number one. That means that for more than 30 years, Honda has made fuel efficiency a priority in our products.

Looking forward: fuel efficiency has become a major focus of every automaker. And that is a very good thing. More fuel efficient vehicles are a win-win for customers and society as a whole.

We're thrilled to see it. At Honda, we love nothing more than a good race - especially when everyone ends up a winner.



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