I currently have a SUMIF function (in Excel) that looks like this (=IF(R1061=0,SU MIF($S$99:$S$19 626,S1061,$P$99 :$P$19626),.
If it helps any it represents this (=IF(WeekEndDat e=0,SUMIF($(PO# )$99:$(PO#)$196 26,(PO#)1061,$( Amount)$99:$(Am ount)$19626),)
So what it does is sum the amounts for every line that has that PO# if there is no week ending date listed, otherwise it leaves a null value.

I'm a beginner at best to Access,...