Add Variance Column to Matrix

Hi bernate 

Please try this:

First of all, I create a set of sample data:

Then create a new table with dax:

Table 2 = {1,2,3}

Then add a measure:

MEASURE =
VAR _newvalue =
    SELECTEDVALUE ( 'Table 2'[Value] )
VAR _columns =
    SWITCH (
        _newvalue,
        1, MAX ( 'Table'[Column1] ),
        2, MAX ( 'Table'[Column2] ),
        3, MAX ( 'Table'[Column3] )
    )
RETURN
    _columns

Then add a matrix and a slicer:

Then add a measure:

% =
VAR _maxvalue =
    MAXX ( ALLSELECTED ( 'Table 2' ), 'Table 2'[Value] )
VAR _minvalue =
    MINX ( ALLSELECTED ( 'Table 2' ), 'Table 2'[Value] )
RETURN
    IF (
        MAX ( 'Table 2'[Value] ) = _maxvalue
            && _maxvalue <> _minvalue,
        1
            - CALCULATE ( 'Table'[Measure], 'Table 2'[Value] = _maxvalue )
                / CALCULATE ( 'Table'[Measure], 'Table 2'[Value] = _minvalue )
    )

The result is as follow:

Best Regards

Zhengdong Xu
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