Loop in Power BI

Hi everyone,
I am starting with dax and I must implement a report to show the diff for all prior month and not only for 'this month' or ' Last month'. As seen in the image, I want the the Remain to show the new diff+priore diff(s)
I assume In order to get the resible result in the Remain I need to create a loop that can get the diff and iterate through all the diff before.

Any help would be appreciated

cheers