Converting 3 steps table to only one table

Hi, 

According to your description and DAX formulas, I can roughly understand your requirement, I think you can use VAR to define the above two calculated tables as virtual tables to achieve the result in one single DAX formula, you can try to create a calculated table like this:

forecasting_uoa_transactions=
VAR  _step1 =
    FILTER ( 
        SUMMARIZE (
            uoa_transactions_history,
            uoa_transactions_history[Date],
            uoa_transactions_history[Country],
            "UoA", SUM(uoa_transactions_history[Total Changes])
        ), 
        DATEDIFF(uoa_transactions_history[Date],TODAY(),MONTH)<variable_uoa_per_cust_window[Variable_UoA_per_Cust_Window Value]+1
)
VAR  _step2 =
    SUMMARIZE (
        _step1,
        [Country],
        "UoA Per Customer Average", AVERAGE( [UoA_per_Customer])
    )
RETURN
SELECTCOLUMNS (
        _step2,
        "Date", [YearMonth],
        "Country", [Country],
        "Customers", [Total Headcount]
    )

And you can get what you want.

If this result is not what you want, you can post some sample data(without sensitive data) and your expected result.

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Thank you very much!

Best Regards,

Community Support Team _Robert Qin

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