I haven't a clue. North Texas is sort of hilly, at least not flat as a pancake, but it won't impress anyone with elevation gain, either, so most people around here don't care. It's just a given that if you ride a bunch, you'll go over some hills, but it ain't the Continental Divide, either.

Something to keep in mind is that people acclimate to where they live, so if you live in hilly or mountainous areas, you're likely to be much better acclimated to hills than flatlanders. People from Mississippi can come out here and think the hills are something terrible, and people from the mountains think it's the flatlands.