Help Filtering

STS_Joshua ,

You can create two measures to achieve amount in 2018 and 2019 seprately:

Customers Amount 2018 = CALCULATE(DISTINCTCOUNT('Table'[Customer]), FILTER('Table', 'Table'[Purchase Date] = 2018))

Customers Amount 2019 = CALCULATE(DISTINCTCOUNT('Table'[Customer]), FILTER('Table', 'Table'[Purchase Date] = 2019))

Then you can create a temp table via click "New Table" using DAX below:

Customers Amount in 2018 not in 2019 = 
VAR Table_2018 = SUMMARIZE(FILTER(ALL('Table'), 'Table'[Purchase Date] = 2018), 'Table'[Customer])
VAR Table_2019 = SUMMARIZE(FILTER(ALL('Table'), 'Table'[Purchase Date] = 2019), 'Table'[Customer])
RETURN
ADDCOLUMNS(EXCEPT(Table_2018, Table_2019), "Date", 2018)

Finanly, create a measure to count customers who purchased in 2018 but not purchased in 2019 in the new temp table:

Customers Amount in 2018 not in 2019 = COUNTROWS('Customers Amount in 2018 not in 2019')

You may also refer to pbix attached.

Community Support Team _ Jimmy Tao

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