Another thing you can do – you can work out your degree days and correlate that with your home heating consumption to see how well your house is performing insulation-wise. Degree days is the sum of (days * degrees C heating need) over time. It allows you to meaningfully compare your energy use from one week to the next when it isn’t the same temperature outside. There is a good explanation of it here
http://www.energylens.com/articles/degree-days