=sumproduct(--(text(a1:a10,"yyyymm")="200610"))
will count the number of days in October.

Adjust the ranges to match--but you can't use whole columns (except in xl2007).

=sumproduct() likes to work with numbers. The -- stuff changes trues and falses
to 1's and 0's.

Bob Phillips explains =sumproduct() in much more detail he
http://www.xldynamic.com/source/xld.SUMPRODUCT.html

And J.E. McGimpsey has some notes at:
http://mcgimpsey.com/excel/formulae/doubleneg.html



MhyphenL wrote:

I have random date ranges over the month break, but I need to get a day count
by month to calculate rev by month.
Eg:
Range: 10/15/06-12/31/06 I need to know # of days in Oct, Nov, Dec from that
range.

Was going to set up one column/month to then put the result into a formula
to figure (total rev for deal / # days in deal)*# of days in deal in that
month=revenue for month

Hope that makes sense.
Any help?
thanks in advance,

--

Dave Peterson