DAX calculation help!

Hi mlmchilli ,

First of all, many thanks to lbendlin  for your very quick and effective replies, and I will give some additions below:

1.Create the sample table.

2.Create the new measure to calculate the margin share.

Margin Share = 
var partn_ = SELECTEDVALUE('Table'[Partners])
VAR Margin = DIVIDE(SUM('Table'[Revenue]), SUM('Table'[Total cost]))
VAR BaseMargin = 0.2
VAR UpperMargin = 0.4
VAR ExcessMargin = MAX(0, Margin - UpperMargin)
VAR SharedExcess = ExcessMargin / 2

RETURN
IF(partn_ = "A", 
    IF(Margin <= 0.4, BaseMargin * SUM('Table'[Total cost]), BaseMargin * SUM('Table'[Total cost]) + SharedExcess * SUM('Table'[Total cost])),
    IF(Margin <= 0.4, (Margin - BaseMargin) * SUM('Table'[Total cost]), BaseMargin * SUM('Table'[Total cost]) + SharedExcess * SUM('Table'[Total cost]))
)

3.Drag the measure into the table visual. The result is shown below.

Best Regards,

Wisdom Wu

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