Orienting the table differently would make it easier to calculate your percent difference in the manner outlined by txnelson.
Using the data you provided, orient the table this way:
![Capture.JPG Capture.JPG](https://community.jmp.com/t5/image/serverpage/image-id/20265i287E08C706585917/image-dimensions/566x191?v=v2)
Now right-click and make into data table. Add a column for the formula that you have outlined (pin-countersink)/pin.
I'm sure there are other solutions, but this one does work.
Dan Obermiller