It’s the end of the school year, and my mind started pondering how many of the students would make it to their 50th reunion. The question is one insurance companies have pretty figured out, but my Google-fu is puny. So I ask The Dope:
Given a random class of 1000 18 year olds in the United States - how many, on average, will still be alive for their 20 year reunion? 40th? After that you get age-related deaths showing up.
Most of them will make it to the 50th anniversary alive. Whether they still want to go is another thing. Also those figures are for 2010 mortality, mortality will decline with medical advances.
Also various things affect mortality and life expectancy obviously. Race, gender, lifestyle, income, education, etc. But people generally don’t start dying en masse until they are 70+.almost 80% are still alive at 70, by 90 it is barely 22%.
Actually doing the math by eyeball from Wesley’s cite:
98% of the 18yos will make it to age 38. 90% of 18yos will make it to age 58. And 1% of their nurserymates didn’t even make it to 18.
I asked a related question a few years ago in this thread, and after someone linked to some data, I crunched through it and came up with this plot of conditional life expectancy. It answers the question, “given that I am currently X years old, what is the probability that I will survive another one/five/ten years?”
We can use that to jump forward ten years at a time, starting with 20-year-olds. From the chart, they have a 98% chance of reaching 30, and then 30YOs have a 98% chance of reaching 40. That means your high school graduates have a .98x.98= 96% chance of being around for their 20th reunion. (in other words, out of 1000 graduates, 960 will still be alive.)
The 10-year survival probability starts trending downward after that. 40YOs have a 95.5% chance of reaching 50, which means your grads have a 0.96*0.955= 91.7% chance of being around for their 30th reunion.
40th reunion (60 years old)? 0.917*0.9 = 82.5% chance.
50th reunion? 0.825*0.8 = 66% chance.
Perfect! Thanks, people. You’ve given me some figures to freak the seniors out with.
Depending on your class size you can have some real sobering fun.
How many of you won’t live to see age 40? For a class size of 25 it’s a coin-toss whether the answer is 1 or 0. For a class of 50 the answer is pretty much 1.
Losing 10% of the class by age 60 is what’ll really get their attention. Better expressed as “Look around the room at all your friends. 2/3/4/5 of you won’t live to see age 60.”
