I am trying to calculate repeat customers after 1st 30 days and 2nd 30 days as separate groups. I have enclosed a link to a table showing new customers and returning customers. Pleae help anyone with any ideas. Many thanks for your help.
https://drive.google.com/open?id=1lK6N56cNyQMOeCMufWi_GGCYg6FNvh5U