Gas prices vary by provider - and each town may have a different provider. Then, the efficiency of people's heating system varies. And how well insulated their home is, and how high they crank up the thermostat.

It isn't the price that I care about, but the usage. I know there's going to be a huge range, but it should give me an idea at least. My hypothesis is that our apartment is very poorly insulated, and that we are paying too much. (It's also unreliable and stops working every other day and we have to call the landlord to turn it on again.)