Dear Power BI community: I would really appreciate if you could help me out with the following issue. I have a table with Customer ID and current month sales, but I would like to have another column with previous month sales for every ID. When I try to do it using an index column, it always calculates the sales from previous month, but it doesn't take into account the customer ID. I'll paste an example of what I'm trying to do above.
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I'm really new to Power BI and I have read about this topic many times, but I haven't still figured out how to deal with clustered indexes or maybe there's an easier way to achieve this. Thank you all!!.
