How to loop date?

[Tharusha.fernando]

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How to loop through dates?

I have an application where I scraped the application date and stored it into a variable. i.e. Date = 1907, format is yyMM as a string. I need to loop the date from one month prior (i.e 201906 if the Date is 201907) until April of the previous year (i.e 201804). How would I do this? Thanks