Weather Multiplier to Predict Your Energy Bill

One user posted: 

"At my house, u can multiply the degree days X 3.74 and it is very close to the energy usage. So I would like to know what others experience. So 30 day kwh divided by degree days divided by sq footage of the home(a home people actually live in)"

Any thoughts, wattvisionaries? Here's the original post with other existing user comments.