In the market for a new or used car that is fuel efficient? Want to know how efficient your current vehicle is? The 2012 Fuel Economy Guide can help. Produced jointly by the EPA and the Department of Energy, this Guide will help you choose the most fuel efficient vehicle for your needs. The Guide can be viewed, searched and downloaded www.fueleconomy .gov and has been updated to include data for new and used vehicles dating back to 1984.