Corporate Average Fuel Economy: How Automakers Rank

While everyone talks about the importance of good gas mileage, unfortunately, there is no gold standard to rank gas mileage among automakers. The best-known effort — though it is not without its detractors — is the government's Corporate Average Fuel Economy program, established in 1975.

Each year, the EPA calculates CAFE based on gas mileage estimates for each car in an automaker's lineup and the number of those cars produced that year. The lineups split into three groups: domestic passenger cars, which includes cars built using mostly domestically sourced parts, from either an American or foreign nameplate; imported passenger cars, built mostly with parts from abroad; and light trucks, which includes everything from pickups and minivans to crossover SUVs, no matter where their parts come from.

Gas mileage figures come from automakers and go to the National Highway Traffic Safety Administration and then to the EPA for verification, so it can take until well into the following year for final CAFE numbers to be published. Based on NHTSA's preliminary data, here's where automakers stood for 2012:

Domestic Passenger Cars
Rank Make CAFE Rating
1. Tesla 111.6
2. Fisker 47.3
3. Honda 37.6
4. Toyota 36.4
5. Nissan 35.1
6. Ford 34.9
7. Volkswagen 33.6
8. GM 32.9
9. Subaru 32.0
10. Chrysler 30.6

All manufacturers encompass their respective brands as of 2012 — i.e., Toyota includes Lexus and Scion.
Source: NHTSA

Imported Passenger Cars
Rank Make CAFE Rating
1. Toyota 46.9
2. Honda 40.6
3. Hyundai 38.7
4. (tie) Mazda 36.9
4. (tie) Subaru 36.9
6. Kia 36.2
7. Mitsubishi 36.1
8. Nissan 35.2
9. Suzuki 33.6
10. Volkswagen 32.9
11. BMW 32.6
12. Ford 31.0
13. Volvo 29.6
14. Daimler 28.3
15. Porsche 27.9
16. Lotus 27.3
17. Jaguar/Land Rover 23.7
18. Fiat 18.9

All manufacturers encompass their respective brands as of 2012 — i.e., Toyota includes Lexus and Scion.

Light Trucks
Rank Make CAFE Rating
1. Mitsubishi 31.4
2. Subaru 30.5
3. Hyundai 29.0
4. Kia 28.0
5. Honda 27.9
6. Mazda 27.6
7. Volkswagen 27.4
8. VPG 27.1
9. Toyota 25.6
10. (tie) BMW 25.3
10. (tie) Volvo 25.3
12. Suzuki 25.0
13. Nissan 24.7
14. Porsche 24.6
15. Ford 24.4
16. Chrysler 24.3
17. GM 23.5
18. Daimler 22.7
19. Jaguar Land Rover 20.2

All manufacturers encompass their respective brands as of 2012 — i.e., Toyota includes Lexus and Scion.

Although CAFE ratings might look like an outright average of the gas mileage for all the vehicles in a carmaker's lineup, it's not that straightforward. The numbers on the window sticker and the ones reported to the government are "entirely separate," a NHTSA spokesman said. City and highway mileage figures come from the EPA's lab tests, with adjustments to replicate real-world conditions. CAFE figures, meanwhile, are derived using different testing procedures and have various incentives built in.

Mileage figures are averaged across a range of engines and transmissions per vehicle, too, so a particularly high- or low-mileage trim level could skew the numbers for an entire car line. Heavy-duty models are exempt from the calculations.

In 2012, the Obama administration announced new CAFE standards that will raise industry-wide fuel economy to 54.5 mpg by 2025. It's important to note, however, that CAFE standards stem from a smorgasbord of 1970s-era fuel economy ratings with various exemptions and credits. Experts say the 54.5 mpg standard will translate to the high 30s in EPA combined city/highway gas mileage on new-car window stickers by 2025.

© Cars.com 11/16/2012