My Mail Rooms are currently overflowing with Unsorted Mail, and I haven't been able to stop it. I currently have 7 Mail Rooms employing 5 Prisoners each, and the prison contains around 650 Prisoners. My [3] Delivery areas are filled with mail, and more comes every day. While the Prisoners are receiving their mail, the amount never seems to diminish.
I have looked online and asked people, but no one seems to know how many Mail Rooms I should provide.
How much mail is received per Prisoner?