All vehicles sold in the U.S starting from this date will carry new labels containing information about type of fuel used, average fuel consumption, fuel prices, total annual fuel costs, comparing estimated five-year fuel costs with those of the average new vehicle and exhaust gas emissions from car use.

This label will also contain a QR Code that can be read by smartphones to directly access sites which provide more detailed information about the vehicle.
The aim is to lead the car shopper to find the cleanest and most-efficient vehicles more easily and quickly, and in this way, make the best choice.

For further information see here.