I used to have a secretary (yes, a secretary, not an "administrative assistant!") who liked to say that "mid-life is always ten years beyond whatever age she was at all times." ?
As far as I'm concerned, there's a lot of evidence that our current human bodies have a maximum age of 120 years so that would mean 60 is mid-life, ya? ?
(And I won't be 60 until 2023! ?)