% difference between years for average sales

Hi mfarali 

According to your description, I made a sample and here is my solution. Please follow these steps.

Sample data:

Create five columns to calculate totals.

Totals = SUM('Tabelle1'[values])

sum of 2018 = SUMX(FILTER('Tabelle1','Tabelle1'[Year]=2018),'Tabelle1'[values])

sum of 2019 = SUMX(FILTER('Tabelle1','Tabelle1'[Year]=2019),'Tabelle1'[values])

sum of 2020 = SUMX(FILTER('Tabelle1','Tabelle1'[Year]=2020),'Tabelle1'[values])

sum of 2021 = SUMX(FILTER('Tabelle1','Tabelle1'[Year]=2021),'Tabelle1'[values])

Create a calculated column to return the % of each year.

percentage = 
IF('Tabelle1'[Year]=2018,'Tabelle1'[sum of 2018]/'Tabelle1'[Totals],
IF('Tabelle1'[Year]=2019,'Tabelle1'[sum of 2019]/'Tabelle1'[Totals],
IF('Tabelle1'[Year]=2020,'Tabelle1'[sum of 2020]/'Tabelle1'[Totals],
IF('Tabelle1'[Year]=2021,'Tabelle1'[sum of 2021]/'Tabelle1'[Totals]))))

Then create a column to return the changes.

change =
IF (
    'Tabelle1'[Year] = 2018,
    0,
    'Tabelle1'[percentage]
        - CALCULATE (
            MAX ( 'Tabelle1'[percentage] ),
            FILTER ( 'Tabelle1', 'Tabelle1'[percentage] < EARLIER ( Tabelle1[percentage] ) )
        )
)

Finally, put "Year" and "change" into the line chart, you will get the result as below.

I attach my sample below for your reference.

Best Regards,
Community Support Team _ xiaosun

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