Ours is always set at 80, the dial is never moved. With it being mid 90's from May through Oct., it's too much of a shock to be in and out with anything cooler. We have ceiling fans in every room and use those if the air isn't cool enough. At 75, I'd be in slacks and a sweater. Plus it's a waste of money. From Nov. to May, it's never on but we use the furnace if we have cold winters and the woodstove doesn't keep the house warm.
When we go up north, we always wear slacks or jeans and take sweaters with us to visit people. Their homes are so uncomfortably cold, like a frozen food locker. It's so beautiful outside, if they just opened windows and got the air moving, they could save humdreds of dollars.