Attached is a simplier version of my sheet that I'm working on. When it's open you are on sheet 1. Under shift c which is in blue for the date of 8-25-10 I have two part numbers listed. I need a formula that will count the three cells. Though there are two part numbers, because they are the same, it count as one. If there was a third and it was different then it would count 2. The count is based off from the letter to the left. Which through the formate of the cell, 1=P and -1=S. Say on is marked with an S and the other is marked with an P, even though they are the same part, it needs to count only 1 becasue I only care about the one marked with P. S means sample, and P means production.

=COUNTIF(X11:X52,"P")