Estimate the number of people since ever?
Estimate the number of people since ever?
This is definitely a top-down (as opposed to bottom-up) sizing.First, I'll assume homo sapiens.
There's a lot of ways to approach this, but I would personally segment it by world population over time. I know that population growth is exponential, and I roughly know the population in different periods - however I have to be careful to account for "existence" i.e. birth/generations.
A lifespan is around 70, but I'll round down to 50 (which averages out across all of time).
If I were to draw this on a chart, it'd be exponential, so I'd a least be comfortable with that.
I'll add 7+4+2+2+3.5+2.5+.5 = 31 Billion people.
However, I know that, for most of history, death rates were absolutely horrid and that something like 50% of all people died before the age of 7. So, I'll multiply 31 billion by 1.5 to get the answer: 46.5 billion people have existed in the world.
Am I close?
(editiert)
Hi Rami,
We are happy to provide you feedback on your solutions.
Would you want to try your best solution first? Happy to improve it together.
Best
Serhat
very close. according to PRB the number is 108 billion. https://www.prb.org/howmanypeoplehaveeverlivedonearth/
When you are looking at current pop of 7B, and then counting up the population of 1960 of 4B, aren't you double counting the people within the 7B group that lived since 1960?