Thanks for your help, but i have another question for you, maybe we can implement your formula in this function. I have a tabe that lists Mailer, and Runtype, I would like to count the unique mailers, that have the Run Type CD, LR, and RU.
I used the following Formula =Dcount("[Mailer]","Daily Reports","[Run Type]='CD'"

+=Dcount("[Mailer]","Daily Reports","[Run Type]='LR'"

+=Dcount("[Mailer]","Daily Reports","[Run Type]='RU'"
I believe this formula will count all of the mailers for the specific Run Type. I will like to incorporate your formula so i can group the mailer, and get the count i am looking for. Is it possible? Thanks in advance