i know the gage can be off by quite a few miles per gallon but i recently made a trip from my home two hours away. averaged around 60-65 mph the whole trip and when i got there the gage read 41.2 mpg. i reset the gage when i left. i did follow a semi all the way there but i think that is still pretty good.
~2011 Ford Focus SES Silver
Plasti-Dip Wheels, H&R Coilovers, Projectors, Shaved Emblems, FSWerks CAI with Race exhaust, Tuned