If that's real, it's crazy good.
I don't have experience with that generation of Civic, but it seems unlikely to be getting THAT MUCH above its highway EPA rating at those speeds, no?
I was prepared to call B.S. / CALIBRATE! 
But then... wait a second! When I looked it up, my old
'winter beater' 2007 Civic 1.8L 5-speed got way above its EPA highway rating at 60/70 mph (70 extrapolated):
Showing both the baseline & modded (
15 mods = 15% MPG improvement: A-B test, 2007 Honda Civic 1.8L, 5-speed) speed vs. fuel economy for this Civic...
2007 Civic sedan 5MT (34 EPA hwy)
But don't forget this car had the light-load-fuel-sipper vtec-e engine.