At my computer it needed 3 minutes and 16 seconds
to complete. I placed the ScreenUpdating inside the
loop so you can see the selection of each sheet.

I believe if you move the ScreenUpdating and the Calculation statements
outside the loop (as I did in my code), your macro would execute quicker.
Also, since you seem to have a workbook set up with example data, after you
move those statements outside the loop and get a new execution time for your
code, would you do me a favor and set the data back up and use my code to
processes it... I would be curious as to the time difference between your
approach and mine (where both are run on the same computer). Thanks.

Rick Rothstein (MVP - Excel)