What percentage of all humans ever born have seen the turn of a millennium, like many of us living today have?(i.e. everyone 15 years or older)

by A_brand_new_me

This question popped up in my head last and made me think that, it probably isn't that high of a percentage.

I'm not exactly sure how you would figure such a number, but I figured if anybody could it would be the fine ladies and gentlemen of this sub.

Thinkyt

Sounds like a question for /r/estimation or /r/theydidthemath...?

tilsitforthenommage

Oh i happen to know this through geography study particularly demographies. The concept you are asking about is called Cohort Survivorship, basically the number of babies that are born, the number that go up their first year minus those that died and so on and so forth till that generational cohort dies out completely.

Usually graphed like this

https://c1.staticflickr.com/3/2070/2163657072_2314f0cec8.jpg

Typically each of the bars goes in a little bit like a stepped pyramid, however with improvements in birthing and health care those steps are smoothing out with some looking like a perfectly coloumn till about 35 with a small decrease at the 20's.

Using information like this you can work out the ratio of survivorship then compare it to how far away the next millennium is and measure it against the population you're interested in. If you are curious still and want actually numbers just let me know, I've a few statistician friends who dig these kind of question, because they are strange creatures.