Take a look at the SUMPRODUCT function. It will be able to do what you want.

http://www.xldynamic.com/source/xld.SUMPRODUCT.html#new
--
Best Regards,

Luke M


"Curtis" wrote:

Sheet 1 column a has sales reps
Sheet 1 column b will contain formula that will add up all sales gather from
sheet 2

Sheet 2 contains source data for entire year however I need to know the
summary by rep for the first 6 months.
Note: column c in sheet 2 has the month

Thanks