Using Excel 2000

I am pulling an inputted number from one cell...call it 15
and an imputted value from another cell...call it $100
What I am trying to do is create a formula that "pastes" the value $100 - 15
times starting in a given cell and moving down by row.
Obviously, both the 15 and the $100 can be changed by the worksheet user.
Does anyone know a simple way to do this?