I believe ps4 can do 24 a year of Sony play the right card imagine a year with a price cut,GTA 6 and a big Sony exclusivity in the same year
PS4 - over 100 millions let's say 120m
Xbox One - 70m
Wii U - 25m
Vita - 15m if it will not get Final Fantasy Kingdoms Heart and Monster Hunter 20m otherwise
3DS - 80m