In the screen shot below, I am trying to get rid of the column on the far right.  I don't want to see a column that Subtotals the Device Count for all months prior.  Any idea how I can eliminate this column without eliminating the individual monthly Device Count Subtotals?  When I go to Data>Sum>Show Total Column, it seems to be all or noting.  If I want to show the monthly Subtotal, it shows the YTD Device Count.

@Doug Copeland, have you tried using the Subtotal option in the ribbon? Not sure if that answers the scenario you're trying to address, but hope its helpful!