I am looking for a function that will group data in a table similar to the
the way this works in Access queries. For example, if I have a table with
one column defined as date, and another column is the amout of money spent,
I would like to be able to put a formula at the bottom of the columns that
will sum the money collumn for each month.

I am familiar with the capability of pivot tables - they work great, but
pivot tables are a bit of a pain to create, and unkeep, etc. I am familiar
with sumif and array formulas to perform this task. Both slow the workbook
to a crawl if you are trying to analyse large datasets.

I am also curious if anyone has a user defined function that if given a
date, will tell you how many days are in the month? For example,
Function(2/13/2004 ) = 29. I can think of a way to do this, but it seems
like I am making the problem more complicated than it is. I suspect that
someone knows an extremely easy way - maybe there is already a funcion in
excel to do this?

Thank you,
Chris