I've noticed this a few times now. If you look up the same car on the EPA's website, it is possible it has different ratings from year to year. I'm aware manufacturers make small changes here and there, but enough to make an almost 10% difference in fuel economy? I just looked up the Civic HX and this is what the comparison showed. I'm not familiar with what changes were made to the HX over these years, but its all the same body style.
