(but you can't use entire col refs in SUMPRODUCT)

Entire col refs are for example: A:A, B:B, C:C
which you can't use in SUMPRODUCT

You need to use ranges such as: A1:A100, B1:B100, etc

by this do you mean that on Sheet2 if I have 50 records
I must use the Sumproduct() in a helper column in each of the
50 rows VERSUS entering it once in a single cell like
a true array-entered formula would do?

No, what was meant was that should you have other values
listed in A3, A4, etc besides 450300 in A1,
e.g: in A3: 500200, in A4: 650200
and you want the same criteria to be applied,
then you could just copy B2 down to B4
to return the corresponding results in B3 and B4

--
Rgds
Max
xl 97
---
GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
----