Count number of rows with multiple criteria

Based on your example:

=SUMPRODUCT(($B$2:$P$2=$C$37)*($B$3:$P$3=$C$36)*SIGN(SUBTOTAL(9;OFFSET($B$4;ROW($B$4:$B$33)-ROW($B$4);COLUMN($B$4:$P$4)-COLUMN(B4)))))

where C36 holds "Ext" & C37 holds 21.

translate SUMPRODUCT, SIGN, OFFSET, ROW & COLUMN as and if appropriate (SUMPRODUKT, FORTEGN, FORSKYDNING, RĘKKE & KOLONNE)