Friday, June 20, 2008
GPM = 1/MPG
One might think of the "fuel economy" of a car as the amount of gas needed to travel a given distance - the number of gallons per mile - which is the reciprocal of the common miles per gallon measure. Discussing fuel economy in terms of miles per gallon is therefore somewhat deceptive - e.g., the improvement in efficiency of going from 25 to 43 MPG is about the same as going from 10 to 12 MPG (in both cases 0.0167 GPM). The Guardian reports on a study by two Duke management professors explaining exactly that.