Too bad we can't convert from propane to lng for rural use.
My savings would be over $700.00/yr.
Here's a savings calculator you can try for yourself...
http://www.peco.com/pecowebsite/peco/html/propane.htm (http://www.peco.com/pecowebsite/peco/html/propane.htm)
Ours is set up a little differently. My house, 8 room two storey was $213.20 total for Jan.,our coldest month. But we have delivery charges. The first 50 ccf is $0.436920, the last 104 ccf is $0.350610, or in my case, a total of 154 ccf at $0.001000 each ccf. to deliver it. The actual gas charge was 154 ccf at $0.94042 or $144.82 so the total was $213.20. I have gas heat, hot water, cooking, and gas dryer so that really isn't too bad, but it's a lot more than it used to be. I think our BTU's are better too vs propane, but I'm not positive about that.