Rolling Weeks

Aryaja96 , if select a date of the week and need more than that, You need and independent date table

Have both table with week rank

Week Rank = RANKX(all('Date'),'Date'[Week Start date],,ASC,Dense)
OR
Week Rank = RANKX(all('Date'),'Date'[Year Week],,ASC,Dense) //YYYYWW format

//Date1 is independent date table 

Last 4 weeks =
var _max = maxx(allselected('Date1'), 'Date1'[week Ranl])
return
CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]>=_max-4 && 'Date'[Week Rank]<=_max))

Need of an Independent Date Table:https://www.youtube.com/watch?v=44fGGmg9fHI

Power BI — Week on Week and WTD
https://medium.com/@amitchandak.1978/power-bi-wtd-questions-time-intelligence-4-5-98c30fab69d3
https://community.powerbi.com/t5/Community-Blog/Week-Is-Not-So-Weak-WTD-Last-WTD-and-This-Week-vs-Last-Week/ba-p/1051123
https://www.youtube.com/watch?v=pnAesWxYgJ8