will do,
one final question with it!at any given time I may have up to 300-400 skus to reference- I tried changing the formula to have the A and B reference A$2:A$300 and same for Bs,
but that doesn't seem to work - what else do I need to change to make it do that? If possible....

Trying to learn the logic by looking at what you wrote, but I guess I have lots to learn in excel