RNI Crystal

Which tables and fields are best and any joins to create a crystal report to display RNI. We can see  PORECLINE ENT-REC-QTY – the Receipt Quantity on PO30  MAINVDTL ENTERED-QTY – The Invoice Quantity on MA43  POLINE VBUY-UNIT-CST – The PO Line Unit Cost So we know if we take Receipt Quantity less Entered Quantity we get RNI Quantity. We can take this against PO Line Unit Cost to get RNI amount. But having trouble with MMDIST and other ways to link data to make this crystal tie completely to the PO135 in non-update. Most records tie out but some don't and we can't see what is making some records that should be on the crystal appear there when on the PO135 but not on the Crystal. We need to add in the daily RNI to a daily Crystal that adds RNI that day to Actuals against GL Budget to get remaining after considering any RNI amounts that day. Any ideas? Thank you!