Driving the speed limit is a little hazardous

In my quest for the maximum miles per gallon to and from work, I am driving at or under the speed limit. The only other people doing that are either 80 years old or driving huge trucks that can't go much faster. It gets a little trick on a two lane highway to pass people when you are only doing 60 or 65. Most drivers are at 75 or more. I managed to crack the 60 miles per gallon mark last night on my way home and then this morning I got 54 on the way to work, which is an all time high. It's only 40 miles each way, so it might not be representative of much other than my commute, but it's still pretty good.