No test can simulate all possible combinations of conditions, climate, driver behavior and car care habits.
Actual mileage depends on how, when, and where the vehicle is driven.
EPA has found that the mpg obtained by most drivers will be within a few mpg of the estimates in this booklet. Factors that Can Raise Fuel Economy Combine errands into one trip. Turn an engine off rather than letting it idle for more than a minute. Get tune-ups regularly. The car will run more smoothly and efficiently.