I am using the following the formula to look at all the orders I have from
2006. I now want to look at each month individually. how can this be done?

=SUMPRODUCT((Sheet1!$F$3:$F$300<DATE(2007,1,1))*Sh eet1!$K$3:$K$300)/SUMPRODUCT((Sheet1!$F$3:$F$300<DATE(2007,1,1))*(Sh eet1!$K$3:$K$3000)*Sheet1!$D$3:$D$300)

I will also need to do this for each month in 2007 as well. But I do not
want to include anything before 1/1/2007.

Thanks
Peter