Require solution for this quey

[Anand_ch]

((Count(DISTINCT (CASE WHEN (`Date Forum Joined` <= ADDDATE(`Date Joined`, 90)) THEN `External User ID` END)) / Count(DISTINCT `External User ID`)) * 100)

[Greg_Deckler]

@Anand_ch Sorry, having trouble following, can you post sample data as text and expected output?
Not really enough information to go on, please first check if your issue is a common issue listed here: https://community.powerbi.com/t5/Community-Blog/Before-You-Post-Read-This/ba-p/1116882

Also, please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

The most important parts are:
1. Sample data as text, use the table tool in the editing bar
2. Expected output from sample data
3. Explanation in words of how to get from 1. to 2.