[Algernon]

Maybe the gauge is off and you are nearly out of gas. Even so, as you did not actually run out of gas, that's pretty good going. So 523 miles using about 20gals comes out to a more realistic 26mpg. Don't think you are lying or have poor memory, just a nice car and careful driving. See how many gals it takes to refill it, and let us know. Well done!