Relative changes graph with first period as base period

Hi  abadi_89 ,

According to your description, I create this data：

Here are the steps you can follow：

1. Create measure.

First find the percentage of the smallest month, convert the percentage of the smallest month to 100%, and compare the other months to change

Measure =
var _Q=CALCULATE(SUM('Table'[Quantity]),FILTER('Table','Table'[date]=MAX('Table'[date])))
var _V=CALCULATE(SUM('Table'[Value]),FILTER('Table','Table'[date]=MAX('Table'[date])))
var _min=MINX(ALL('Table'),[date])
var _3Q=CALCULATE(SUM('Table'[Quantity]),FILTER(ALL('Table'),'Table'[date]=_min))
var _3V=CALCULATE(SUM('Table'[Value]),FILTER(ALL('Table'),'Table'[date]=_min))
var _value=DIVIDE(_3Q,_3V)
var _percent=DIVIDE(1,_value)
var _result= DIVIDE(_Q,_V)*_percent
return _result

2. Result

You can downloaded PBIX file from here.

Best Regards,

Liu Yang

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