I found a work around by taking adding a column with the following formula
=text(A3,"mmmm"). This converted the date ranges to the proper month and the
completed my sumif function based on the month name.

Dale

"Dale" wrote:

In column A I have dates for the entire year in one week increments, I.e
1/1/2009, 1/8/2009, etc.. In column B I have the number of customer acquired
during that week. I want to now sum the number of customers by each month.
This will allow me to develop acquisition nnumbers against marketing pieces
mailed each week instead of totaling them for the month. I am looking for a
sum feature that will read and sum values within the range of 1/1/2009 -
1/29/2009, 2/5/2009 - 2/26/2009, etc..

Any suggestions?

Thanks

Dale