> Personally I think it's useful to use scales & dimensions people already know & grasp. To the best of my knowledge, most of the world reports transport effic

> Personally I think it's useful to use scales & dimensions people already know & grasp. To the best of my knowledge, most of the world reports transport efficiency in l/100km. And the poster even nicely included the US-centric mpg value for people in not-most-of-the-world.