For the cells that are in a different format, how do you wish to process them?
--ron

Yes, I'm banging my head on this.
I've got big majority of values in xx-yx format X-number, Y letter,
which is already correctly processed by the formula. Some are
xx-yyyyy+, which also gets through and some xx-y, the same without
error. Unfortunately I've got also 0, ', and empty cells. These,
especially empty cells, cause problems. It would be the best if these
got totally ignored.

What i did was combine the formula with COUNTIF(a1:a10;"*A*"), to count
the number of these occurrences, which also includes cells that only
contain this letter, but were not summed. I got much better result with
"*-A*", but I found at least one cell that had -A in the wrong place,
so it was also not calculated.

Is there an easy way to only use xx-yx format, also count the number of
those used and ignore 0 end empty? I don't seem to be writing my if
clauses correctly.

Thanks