[All games are rounded up/down by the year]
I really hope Treyarch are given an uninterrupted three years for their next iteration of zombies, it can easily be argued that the reason there's a lot of hiccups in zombies was due to the quantity>quality approach by being assigned to work on Vanguard and MWIII zombies.
Chronicles is a major asterisk given that is undoubtedly took away additional resources from BO4 zombies.