ArviLaanemets: Thank you for the suggestion, and for the point about design. I completely understand your poor design comment, but in this case, your solution will not work for me. I am creating a tool for myself to use, so I don't mind it being a little clunky as I don't have to worry about user error.

Xor, this is exactly what I needed, and it works perfectly! Thank you so much! I never would have thought of using OFFSET.

Thanks again to both of you for your responses!