Percentage Difference always blank

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.

zaidkhusain , The information you have provided is not making the problem clear to me. Can you please explain with an example.

If you are looking to take diff % between last date and this date, check the method given in

Power BI — Day Intelligence Questions — Time Intelligence 5–5
https://medium.com/@amitchandak.1978/power-bi-day-intelligence-questions-time-intelligence-5-5-5c3243d1f9
Appreciate your Kudos.