Hello JP,

...
You have a point with your remark on the company policy. Although not
explicitly forbidden, our IT department will not support it.

Therefore, I used the function that T. Valko suggested.
...

Ok, since you ticked the first point off, have a look now at the
second one of my Excel Dont's, please:
http://sulprobil.com/html/w-rule.html

Avoid array formulas you (or the majority of your colleagues) do not
understand or which you will fail to maintain later on.

My thesis is that there are brilliant people around here suggesting
nifty (array) formulas. But 95% (hmm, maybe even 99%) of all Excel
users do not fully understand them, and the (array) formulas are not
tackling the right problem space anyway. A huge bulk of the questions
here can and maybe should be reasonably answered with Pivot tables (I
suggest to search for Herbert Seidenberg's Pivot table solutions
here). And another nice part of the challenges can be solved with VBA
macros which encapsulate the functionality so that the casual user can
easily use them (I suggest to have a look at my website). Before you
"give in" to an array formula I suggest to think about helper columns
and normal worksheet functions.

Maybe you are satisfied with Biff's suggestion for now. But I suggest
to put my suggestion into a cell comment next to his formula. I bet
somebody will struggle with the array formula later on.

Kind regards,
Bernd