CombinationMeasure =
IF (
    ISFILTERED ( '1_Table Matrix'[Dimension] ),
    SWITCH (
        VALUES ( '1_Table Matrix'[DimensionType] ),
        "Revenue by segment",
            IF (
                VALUES ( '1_Table Matrix'[Dimension] ) = "Total",
                [Revenue],
                CALCULATE (
                    [Revenue],
                    Dim_product[Segment] = VALUES ( '1_Table Matrix'[Dimension] )
                )
            ),
        "Price by segment",
            IF (
                VALUES ( '1_Table Matrix'[Dimension] ) = "Total",
                [AveragePrice],
                CALCULATE (
                    [AveragePrice],
                    Dim_product[Segment] = VALUES ( '1_Table Matrix'[Dimension] )
                )
            ),
        "Transactions by country",
            IF (
                VALUES ( '1_Table Matrix'[Dimension] ) = "Total",
                [NumberOfTransactions],
                CALCULATE (
                    [NumberOfTransactions],
                    Dim_geo[Country] = VALUES ( '1_Table Matrix'[Dimension] )
                )
            ),
        BLANK ()
    )
)
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