Hi, I'm using the trusted =IF(SUMPRODUCT(($A$2:$A2=A2)*($B$2:$B2=B2))>1,0,1) formula but with large amounts of data, it's absolutely crushing system performance. I'm using the formula in a helper column of a source table to populate a column in a Pivot.
This is in Excel 2010.
Is there a VBA...