When I did my last post I incorrectly put 29.7 instead of 26.7. Went back and made the correction. However, I did drive on a 55 mph highway and set the cruise at 57 mph and got 31.9 mpg. This is not a misprint. I live in Florida and the roads are very flat. This 31.9 mpg was a hand calculation. I did the calculation 3 times to make sure it was correct. Needless to say I was very surprised at that number.