I have a data set and I want to break it down in groups based on order dates. The problem is that I have some dates that are Null. Right now my calculation is :
IF [OrderDate] > [QuoteDate] AND [OrderDate] < [ExpirationDate] THEN "Closed" ELSE "Not Closed" END
But the problem is the "Not Closed" group includes dates that fall before and after the quote date to expiration date range, but it includes the Null date values. I want to make those values a separate group. Is there a way to add to this calculation something like : If OrderDate is Null then "Null Group"
so my filter would then have 3 categories Closed, Not Closed, and Null Group.