Here's the deal. At night I run the temp down to 72 degrees F. During the day I let it go up to 76. Is there a formula that shows the most efficient way to allow for temperature variations? In other words, am I saving energy by allowing the temp to go up to 76 during the day, just to run it back down at night, or would I save more money overall, by say letting it go up to 74 or higher say 78 during the day instead? Get my drift? I assume that if I'm going to run the temp back down, the best time would be at night, but would it be better just to keep the temp the same all of the time? I'm thinking no. Thoughts? Thanks!