The similar issue was noticed and fixed earlier for the user profiles.
But it still can be seeing on the StackExchange "All Sites" page. I almost sure that is was already submitted here, but i cannot find any question about this. And, yes, I understand that 12 months are most likely 11 months with some additional days, and 1 year is 1 year with some additional days, but when you see it on the screen, it looks a little bit odd.