this should help.
=sumproduct((year(daterng=year(a1))*(month(daterng =month(a1))*rngtosum)

--
Don Guillett
SalesAid Software
Granite Shoals, TX

"Trevor Shuttleworth" wrote in message
...
I'd be grateful for your assistance please. I think I should know how to
do
this, but I don't. Hopefully you can save me a lot of time.

I have a column (A) on one sheet, "Summary", which contains dates, April
2003, May 2003 and so on. The cells actually contain 01/04/03, 01/05/03,
etc. (UK date formats)

On another sheet, "Solutions", there is a column of Invoice Dates (D) and
a
column of Invoice Values (F).

In column C on the Summary sheet, I want to subtotal the Invoice Values on
the Solutions sheet where the Invoice month and year match the month and
year in column A on the Summary sheet.

I think I should be using SumProduct or an array entered formula but I
can't
quite get my head round it.

I appreciate your help, thanks

Trevor