"TIMOTHY" wrote in message
Thank you Peter, dpb, and GS

Probably a bit more than you bargained for:)

dpb is of course right clarity is important, particularly when coming back 6
months later. In typical use it's unlikely you'll notice any difference
between N or -- (or similar) so go with whichever you prefer, but keep in
the back of your mind if ever dealing with heavy calculation why they are
not quite the same.

More importantly understand why it's needed, namely because Sumproduct
treats any non-numeric array elements (after resolving) as zero. That's
useful for text but we want any False/True as numeric 0/1

Peter T