how bad was the gas reformulations due to EPA restrictions, on mpg? Gerald kept track, it was startlingly bad

He bought a 1987 Ford Escort new, and it got 37 mpg
then a couple years went buy and the EPA regulations caused a reformulation,  and his mpg was 24
Then a year after that, a 2nd reformulated fuel was put out, and then he only was getting 19 mpg

Gerald Foye
AAA Westways magazine, letters to the editor, Jan Feb 2012 issue