How to get 4 weeks rolling average?

Hello there, 
I am trying to get the 4 week rolling average for revenue in 2022. 
I have dataset that looks like this:

Notice that i have two different channels from which my revenue is generated. 

So what i need to produce is a table that will look like this:

Basically i have to calculate rolling avergate for each channel and store it for each of my fiscal weeks.

I know how to do this in python but i need to get this to work in Power Bi. 

Here is the link to my pbix and excel files:

https://1drv.ms/u/s!AhhZq1add5YwjoV7tAhrdGuZOAyN3A?e=ds4QiZ

Thank you so much.