That is quite a complicated way to calculate the CAFE standard. I wonder what the definition of "light truck" is? CAFE doesn't help day to day either. When you

That is quite a complicated way to calculate the CAFE standard. I wonder what the definition of "light truck" is? CAFE doesn't help day to day either. When you buy the car is when you are thinking most about gas prices and fuel efficiency. When gas prices are high people buy fuel efficient cars. The Prius, Teslas, etc. already exists so people can already show preference for fuel efficiency and manufactures can follow. Edit: I was just thinking, if you force high fuel efficiency on the fleet and people want cars/trucks on average that get worse fuel efficiency than the stated goal, the market is going to always make the gas guzzlers more profitable and the fuel efficient cars loss leaders. We should either tax the gas or have a sliding scale tax on cars depending on the fuel efficiency. And taxing gas is better. I'm sure fuel efficiency standard can be gamed like diesel gate more easliy than the volume of a gallon of gas.