DAX causing problems calculating dynamic indices base 100

I think if you try changing the aggregation functions MAX instead use SUM.
From the suggestion you have shared - I think if you make these changes your output will change - as when you select multiple member types it has to get the sum instead of maximum value.

Index Local dept = 
VAR Date_index = MIN ( 'Calendar index'[Date] ) 
RETURN SUM ( 'Index local'[Member count] ) 
/ CALCULATE ( MAX( 'Index local'[Member count] ), 'Index local'[Date] = Date_index ) * 100 

Index Union = 
VAR Date_index = MIN ( 'Calendar index'[Date] ) 
RETURN SUM( 'Index Union total'[Member count] ) 
/ CALCULATE( MAX ( 'Index Union total'[Member count] ), 'Index Union total'[Date] = Date_index ) * 100 

 
EBoklund 
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Hi EBoklund ,

I have not had a look at the pbix you shared but I am sure you are facing the line issue because it does not have row context to it.

I tried creating the same in a blank file and i am able to see indexing fine.

I think what you need to do is create a calendar table which is related to both your aggregated tables and then only use the dates from that calendar table on the visual - this way both your table's measures / columns you use will have filter context on what dates are queried on the visual.
Note, this calendar table is different than your static choice of index date "01/01/2021".

For now, to prove my point if you try to change your selected date column in chart from one table to another your bar or line data will not give you the expected result.


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