TOP 10 countries using DAX code

Anonymous it should work :))

What is [Att_Value1]? Is that a column or a measure?

Anonymous no worries 🙂
This is for the scenario where the total is for all (just change it to your names and 10 instead of 3):

Top 3 Countries By Sales = 
VAR _countries = TOPN(3, ALLSELECTED(Customer[Country]),[Sales Amount])
RETURN
    IF(
        ISINSCOPE(Customer[Country]),
        CALCULATE(
            [Sales Amount],
            KEEPFILTERS(_countries)
        ),
        [Sales Amount]
    )

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