This is a difficult problem. In the past I had developed a formula-only
solution for FIFO valuation, but it was for pricing only. I have it
somewhere in my home computer. It was based on a prototype data layout.

If you want, you can send me your file at the following address:
vezerid AT act DOT edu

I don;t promise anything, maybe someone else in the group will jump in
anyway, but unless I have an example of the actual data I can certainly
not suggest any solution at all. It might well be VBA business, esp.
depening on your needs.

Regards
Kostis Vezerides