Miles Per Dollar

I think that instead of advertising a car's efficiency in MPG it should be measured in MPD ( miles per dollar. ) That way whatever the power source ( electric, gasoline, hydrogen, or natural gas ) you'd have an easy basis for comparision.

I realize that MPD is very with respect to where you are in the nation and the current costs of energy in that part of the nation.

So, right now, my car gets 9.17 miles per dollar. How far does a dollar take you?

For the daft: MPD = MPG / (Current Price Of Gas Per Gallon)