Hi Davide @damarino ,
Since PercentileRank is in play, it is very much dependent on your data.
(Say for example, you might have only one record per country per region for a single day
vs Sample data that we use to mimic your problem might have more records per day.
Such differences will cause differences in the end result.)
So, Please create a sample dashboard showing your problem state using Arena and post it here.
(Details on using Arena can be found here - QuickSight Arena )
We will take a look once we have the sample from you.
Regards,
Arun Santhosh
Principal QuickSight SA