Those are old EPA numbers, real life mileage can be big differen
The new EPA system is slated to start on 08 model years. The biggest hit is those hybrid cars, about 25-30% drop.
Click for details" target="_blank" >Click for details
The real world mileage is probably the best to measure the gas consumption; take EPA numbers for reference only. My neighbor has a Prius. He told me he could only get 40 mpg max.