We didn't have hard numbers a few days ago when we broke the news about the government's proposed changes to Corporate Average Fuel Economy standards. Now we do. Road&Track has a breakdown of the increases for each class, inclusion in which is determined by a vehicle's footprint, or its length times width. For instance, the smallest of the six classes will be those vehicles whose footprint is smaller than or equal to 43 square feet, while the largest class will be those larger than 65 square feet. The article also details the CAFÉ targets for each class from 2008 to 2011 when all automakers must comply with the new standards. The smallest of the six classes will be subjected to the largest increase, going from today's current standard of 21 mpg all the way up to 28.4 mpg in 2011.