Biff wrote...
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How would you count EMPTY cells? I haven't been able to figure it out.
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Presumably you mean cells containing nothing. If there were another
column in the filtered table that always contained something, then

=SUBTOTAL(3,OtherColumn)-SUBTOTAL(3,GivenColumn)

would count the number of cells in GivenColumn that contain nothing. As
for cells that contain things that evaluate to "", counting them
requires udfs.