Why are some "best mpg" stats insanely inaccurate? On the recent activity area, it said a driver named Pearhead had a "best mpg" for their Honda Odyssey at 114.9 mpg! When you go and look at his/her trend, the highest mpg achieved on that vehicle was around 20+ mpg. Also, there is nothing on the stats page that indicates 14.9 mpg.
A lot of times this happens because someone enters in bad data. They get the feedback that tells them they just got 114 MPG, and then they go in and fix it. You probably saw it between the time they posted it and fixed it.