This is a stupid easy problem I'm sure but I need help.

I have =Month(Today()) which gives me "1" for January.

but I am looking at a 3 month window behind me that shifts with each current month. so if it's January I am looking at Oct - Dec. so if today is 1 for January I actually need it to display 10 for October.

I have accomplished this by using =Month(Today()-90) but I fear that it may eventually display the wrong data because not every month has 30 days.

When I use =Month(Today())-4 it gives me "-3" which isn't helpful and when I place it inside the () it still gives me a "1" which also doesn't help.

Thanks in advance.