If you are looking to ignore the hidden values try the below

=SUMPRODUCT(SUBTOTAL(3,OFFSET($C21:$C1006,ROW($C21 :$C1006)-MIN(
ROW($C21:$C1006)),0,1)),--(O21:O10060)*(N21:N1006=0),$C21:$C1006)

If this post helps click Yes
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Jacob Skaria


"Bec" wrote:

I have the following formula and would like to use a subtotal, can anyone help?

=SUMPRODUCT((O21:O10060)*(N21:N1006=0)*($C21:$C10 06))

Essentially the formula is counting addition of vehicles in the current
month. i.e. Counts if the col O0 and col N equals 0