Yes, I think your calculations are correct. With the anthracite coal price increase, natural gas is becoming more attractive. I still plan on burning anthracite coal, but only in the few weeks of really cold weather, just because the comfort level of anthracite coal is hard to beat. But if the price difference between anthracite coal and natural gas gets much wider, I'll be stock piling more wood. I can't believe how much anthracite coal has increased since I started burning it a few years ago. I love anthracite, but I'm now getting concerned that it may not be an economical option in the future. I may have to use natural gas and wood to save money on home heating costs. Who would have belived that I would be even saying this. Wake me up from this bad dream!