This may or may not help - but if you want to just "count" the ones who have
it and subtract from the total, try this.

make a column that you can just insert a simple text "X". That's your counter
At the bottom use =count( ) put the full range in here.
It will then only count the "X"'s and not the blank spaces.
If you do this on some other column that has to be filled in, then you'll
have two counts. One - the account totals and two - the "X" that shows which
have the upgrade.
Subtract the two and you have the difference.
You can also sort by the "X" and see who has/has not.

yes/no/maybe