Below I have a group of Cells in Columns A & B. They represent backup tape
numbers and a description. I need to build some kind of a statement that
will tell me the last tape numbe in each set. A set consists of tapes 1 thru
# where # could be 1,2,3 or 4. Some sets have 1 of 2 others have 1,2,3 of 4.
In the first 4 records the last tape in that sequence would be 200507

The formula would go in Col. C and I showed what the results should be
(manually entered)

I have tried using vlookup and building an IF statement but I hit the max
of the If's.
Any ideas would be appreciatied.

here's the data:

Col. A Col. B Col. C
tape # Description Master
200504 Feb 2004 Onsite Tape 1 of 4 200507
200505 Feb 2004 Onsite Tape 2 of 4 200507
200506 Feb 2004 Onsite Tape 3 of 4 200507
200507 Feb 2004 Onsite Tape 4 of 4 200507
200584 Feb 2005 Offsite Tape 1 of 2 200586
200586 Feb 2005 Offsite Tape 2 of 2 200586
200775 Feb 2006 Offstie Tape 1 of 3 200777
200776 Feb 2006 Offstie Tape 2 of 3 200777
200777 Feb 2006 Offstie Tape 3 of 3 200777