What solved problems yesterday will block progress tomorrow. Recognize that change that matters involves a complex system of influence that has more to do with history than anything intrinsic to the problem space.
With rising gas prices consumers are encouraged to shop for improved miles per gallon, MPG. This leaves their own behavior out of the equation. Better to improve miles per month or better gallons per month. When normalized to national observed full-time monthly millage (1000 miles/month) one can then compute full-time equivalent MPG that reaches into the hundreds.