My baseline for a 2300 sqft, 1980 cape on the midcoast was about $65/ mo. Oil hot water, line dry in the summer, 2 teens 1 adult. Have installed 5 heat pumps but they weren't all online until about Xmas. One was, and I wanna say December bill was about $90, but I like to only pay my bill every few months so I'm not really sure what December's share was. Also use a wood stove. Sorry, I'm not at all helpful!

I enrolled in CMPs energy monitor thing, where I can view usage daily. Maybe try that?