Filled up today when I noticed Bloomberg's reporting on oil prices rising again. Ended up with 17,93mpg. That boosted my lifetime average in the Mustang to 15,02mpg, beating my 15mpg EPA guesstimate! My 90 day average is looking pretty as well!
(yes, I know legislation that created the EPA wasn't even passed for another three years after my car was built. 15mpg was a rough average for V8 '65-'68 owners' FE, so I took it as my own starting benchmark to beat)