Life expectancy in the United States is now 81 for women, and 76 for men. That's assuming you live a normal life, stay married to the same person, have kids and grandkids, work hard, go to church, blah, blah, blah...
Then there are the ones that live fast, and die young. You know who they are.
Finally, we have the old hard cores. People who have lived crazy lives, booze, smoking, and drugs up the ass, yet they're still alive and kicking.
For example: Willie Nelson(89), Bob Dylan (81), David Crosby (81), Mick Jagger (79), Keith Richards (78), Debbie Harry (77), Jim Hamilton (76).
It's like they have a genetic and spiritual disposition to survive, no matter what they do to their bodies and minds, over the years.