COUNTX (Column with multiple duplicate values)

[paz_23]

Hi, 

I am still very new to DAX and I am currently trying to get better with the formulas. My questions is that I have a column [Reference Numbers ] that has various duplicates due to itemization but on the below table I want it to tell me the disitinct reference numbers for the locations for 2021 and 2022. Below are the formula that I currently have but as seen I am getting a result of 902 for 2021 when it should be 395. All help is appreciated! 

[olgad]

Please kindly accept the solution since it worked for you. Thank you

[olgad · Accepted solution]

Calculate( DISTINCTCOUNT('ClaimsData'[Reference Number]), Filter('ClaimsData', 'ClaimsData'[Year]=2021))

It would be great if you were using a separate data table thats a basis of any report.
Here you can read more on that https://learn.microsoft.com/en-us/dax/calendar-function-dax