Received help with this one before (see Excel Formula - 5/3/2006) and now the
formula works great for the worksheet labelled "Correction Values". But now,
almost the exactly same scenerio with a worksheet labelled "Density Chart"
but I am getting a #VALUE! error.

Are my eyes just tired and I'm missing something?
=SUMPRODUCT(('Density Chart'!A3:A9427=B3)*('Density
Chart'!B3:B9427=B4)*('Density Chart'!D3:D9427))