In order *not* to confuse SUMPRODUCT, we use semicolon as argument separator when comma is used as digit grouping symbol.

e.g.

=SUMPRODUCT(--(A1:A10=123,45);--(B1:B10="abc");C1:C10)

However, we use the plus sign (+) to indicate both OR and ADDITION.

e.g.

+ used for "addition"

=SUMPRODUCT(--(C2:C31="TLG"),--(H2:H31="TLG"),D2:D31+I2:I31)

+ used for "or"

=SUMPRODUCT(--(((A1:A10="Ford")+(B1:B10="June"))0))

I guess SUMPRODUCT knows that the "+" means "or" because of the equal sign (i.e. logical test)? Why not use double plus (++) for "or" test? Just a thought. Don't mean to confuse anyone.

I find all this interesting.

Epinn