Hello, other than Excel, Calc does not recognise the pattern if it is not previously formated as date. So you could format say two first cells as date in the desired format, enter two first valid dates, which will be reformated as just defined and than you can use the autofill function. (Mark the two cells with the pattern, left-click on the small dot on the right lower corner, drag this down.) See attached screenshots.
The desired format of the cell can be done by formating the date style.
Of course it’s MM/YYYY for your language.
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