Good grief.
In my last place, after my roommate left, I kept it at 76F, except at night when I'd drop it to 68F. This is all during 0 - 20F weather.
My apartment is so well insulated that I keep the heat at 62F and I'm still running around in shorts and a t-shirt in here. And it's been between 0 and -20F since we moved in.
Luckily I don't pay the heat bill here.