Hi,
It is only dynamic if you use rolling dates.
If you click for example on "Prior month to this date range" it won't be hard coded but if you select a specifi period it will be hard coded.
For MoM changes, I created a date range as follows :
Start : start of current month minus 28 days
End : start of current day minus 28 days
For YoY, try this :
Start : start of current year minus 1 year
End : start of current day minus 365 days