I have been struggling with what I feel should be a fairly simple problem and am going around in circles at this point. I have some data relating to application processing times. The main table contains application start and completion dates, and I am trying to get a count of the number of applications which are active (ie. started but not yet completed) at the end of a given quarter. Missing end dates indicated that the application is not yet complete. I have an aggregated table which contains quarter end dates and some other data which has been aggregated from the main table. I want to add the count of active applications for each quarter end date to this table. See sample data below. Help would be appreciated!
I would probably approach the problem that way: