This is something I've always found strange.
COUNTA will consider ="" as NOT Blank
However
COUNTBLANK will actually consider ="" as Blank.
I don't really care either way, if Excel says it's not blank, fine.
Or if Excel says it IS blank, fine.
Either way, But both functions should consider it the same..
Anyway, off the soapbox.
With that in mind, since countblank actually DOES consider ="" as blank, then you can do this as well
=10-COUNTBLANK(A1:A10)
The 10 should be equal to the number of rows considered in the countblank.