Newdoverman,
Not the OP, but....
Maybe I'm doing something wrong, but when I tried using Today(),(to help OP out) it would return a very odd date, like 1/10/1900. It's probably because I am doing something wrong.
My thought was to add a start date column (as you suggested) like column A then use....
=Days360(A7,C3)
But, as I am a novice, this might be the wrong approach...your thoughts?