It is a bit more complicated than that, car makers do the test themselves, EPA can spot check, and manufactures can choose between two methods, one of which com

It is a bit more complicated than that, car makers do the test themselves, EPA can spot check, and manufactures can choose between two methods, one of which comes up with a bigger number, and is reflective more of city driving than highway driving. imho, I fault the EPA for not having a sensible highway range/city range as a standard, then none of this would be an issue