the Active calculation uses a rolling average table calc, when =0 then 0 else 1, to make it work however you have to set the table to show empty rows.
the new customer calculation uses an LOD to get the earliest sale date then compares the current month to that and sets to 1 if they match.
Created in the attached workbook.
211633SS.twbx 72.5 KB
Many thanks. This was exactly what I was looking for.