I'm having a block. I was trying to find First Time Buyers or those folks who have not attended in the last 5 years. So I did a simple list looking at the Ticket History Perf Date (and I've done with unique perf =>1 and another without).
I then take that list and create another list of this FY performances and ask for those that does not have the list of prior ticket buyers.
However, when I run it in T-stats, I'm still finding folks in the list that have prior ticket purchases in the 5 years I thought I was suppressing.
What am I missing? Is it because history doesn't have the future performance dates yet? Thanks