Calculating prior month values

Hi, kiril ;

You could combine this excel files in power query .

https://docs.microsoft.com/en-us/power-bi/transform-model/desktop-combine-binaries

1.Put all your workbooks in a folder, then click Get Data->Folder-> Edit.

2.After step 1, click context column then click Combine Files like below:

3.Choose which type of sheet you want to combine to a single table, here I choose Sheet 1, it means sheet1 in all the workbooks will be combined to a single table:

4.The result is like below:

5.In desktop, we could use matrix.

Best Regards,
Community Support Team _ Yalan Wu
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