Hi, I have a table and want to show the quantity (of tickets sold) in the previous event (I compare the event_code of this year with the one of the previous year). Normally this formula works for other linegraphs but in this case it seems it doesn't get the nulls as there are something like 500, and it says there is not any null.
This is the expression:
Sum({<year_event=, month_event=, event_code=p(previous_event_code), event_to_compare=, event_name= ,customer_country = {*}>} quantity)
Any ideas?
Cheers
