This becomes, when viewed daily:
Dcount("*", "filtertable1", "unitprice <= " & filtertable1.unitprice & " AND orderid= " & filtertable1.orderid & " AND odate = " & Format(filtertable1.odate, "\#yyyy\-mm\-dd\#")) AS PriceRank
The calculation of PriceRank via DCount has a systematic performance...