Count a row if the identifier did not appear before

[Anonymous]

Hi, i was developing a dashboard to see the use of an App:
I want to create a measure to see how many new users are using the app. Example:

Date of Login | User Identifier | 

9/8/2023              1

9/8/2023              4

9/10/2023            1

9/10/2023            4

9/10/2023            6

If I am standing in 9/10/2023, there are only 1 new user (User identifier: 6 )
I want to create a measure to count that the number of new users for a specific date.

Thank you so much!

[parry2k · Accepted solution]

@Anonymous you can add a measure something like this:

New Users Count = 
VAR __UniqueUsersFromCurrentDate = CALCULATETABLE ( VALUES ( NewUser[User] ), FILTER( ALL ( NewUser ), NewUser[Date] < MAX ( NewUser[Date] ) ) )
VAR __OnlyNewUsers = EXCEPT (  VALUES ( NewUser[User] ), __UniqueUsersFromCurrentDate )
RETURN COUNTROWS ( __OnlyNewUsers )