Try one of these:

=SUMPRODUCT(--(WEEKDAY(A2:A20)=2),D2:D20)

=SUMPRODUCT(--(TEXT(A2:A20,"ddd")="Mon"),D2:D20)


--
Biff
Microsoft Excel MVP


"al" wrote in message news:djSDj.2924$bN3.2476@trnddc03...
Hi,

In a worksheet I have dates in column A (format
03/18/2008,/03/17/2008,03/17/2008) and in column D i have numbers (format
0.4,1.0.3).

I am looking for a formula to total all of the numbers where the date
happens to be a Monday - example:

Column A Column D
3/17/2008 0.5
3/17/2008 1
3/18/2008 2

I would like a formula that returns "1.5" because 3/17/2008 is a Monday.
Any ideas?