I suppose you are right, but I hope not. I really can't attach any files that would reveal the complexity. There are hundreds of part numbers, and periodically, part numbers are added (not in sequence), and it makes the most sense to insert them in between other part numbers. But when that is done, it changes the cell addresses of all cells below. And those cells are linked to 6 or 7 other excel files that use their data. I was really hoping to be able to keep the accurate information flowing even when cell addresses change. If you or anyone else has any suggestions, it would be so helpful.