SD
=SUMPRODUCT(--(A1:A18<=E1),--(A1:A18(EDATE(E1,-6))),B1:B18)

Change the -6 to -12 and -24 for the other months


=SUMPRODUCT(--(A1:A18<=TODAY()),--(A1:A18(EDATE(TODAY(),-6))),B1:B18)

Same formula, except the current date is today.


"Skydiver Driver" <Skydiver wrote in
message ...
I am trying to figure out a way to add one column based on the date
entered.
I need to write a formula that will calculate the past 6,12, and 24 months
from the current date.

Travis