5-Day Moving Average

ripstaur - I like Fowmy 's solution, seems like it should work. Nice and simple. There is a Quick Measure Gallery submission that should work as well.

https://community.powerbi.com/t5/Quick-Measures-Gallery/Rolling-Average/m-p/160720#M3

Could also be done without the time intelligence functions if necessary (in an RLS or Direct Query situation), in theory:

Moving 5 Day Average =
  VAR __MaxDay = MAX('Table'[Date])
RETURN
  AVERAGEX(FILTER(ALL('Table'),[Date]<=__MaxDay && [Date]>=__MaxDay-5),[Value])

You may find this helpful - https://community.powerbi.com/t5/Community-Blog/To-bleep-With-Time-Intelligence/ba-p/1260000

Also, see if my Time Intelligence the Hard Way provides a different way of accomplishing what you are going for.

https://community.powerbi.com/t5/Quick-Measures-Gallery/Time-Intelligence-quot-The-Hard-Way-quot-TITHW/m-p/434008

But, ultimately, actual sample data would be tremendously helpful to be very specific with a solution.

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.