Hi All,I'm trying to sort a way I can get a count of the unique users/return users in a month.

Users are identified by the UserUuid column and can access multiple times in a month
I need to create a monthly count of the number of unique/distinct users (UserUuid) that have not accessed the service in a prior month. I can't subtract the previous months distinct count as not all those Users would have accessed the system the following month.

In the below example for June of the 6,00 users 3,500 users of the 4,000 for May are returned users so I have 2,500 new unique users.



This is the end result I need
Month Total Users Identified Previous Users Unique Users
May 2019 4,000 4,000
June 2019 6,000 3,500 2,500
July 2019 7,500 6,000 1,500
August 2019 15,000 7,500 7,500

Any help is appreciated.

Cheers

DeanMcK