The Lancet: World population projections by 2100
thelancet.com
thelancet.com
The big surprise being China,of-course. A drastic decrease projected in the coming 80 years.Should have policy consequences as well, I would think.
If you compare https://www.populationpyramid.net/china/1980/ with https://www.populationpyramid.net/china/2020/, you see how drastic its effect on China’s population pyramid was. Drastically fewer kids means fewer parents 20-30 years later.
(There also is a bit of an effect of richer people having fewer children, but for China, that effect is relatively small)
Can you clarify on what you mean by that please? Are you referring to pollution an environmental degradation?
Think of the percentage of any modernizing economy that goes into things like food and clothing for children, education and educational materials, transport, energy consumption. The reduced output of parents who are tired from looking after or arguing with children. And this is for something that won't start putting value back into the economy for a good 18 years from initial investment.
Skip this, and instead of food and clothes for children adults can spend on housing, transport, take risks with starting businesses without the chance of hungry dependants, etc
1B feels like a lot more realistic estimate than 750M.
As I understand it, before the industrial revolution, the population was what's described as Malthusian. As a country became richer it tended to have a population increase, which meant that an estimate of GDP per capita remained relatively similar. Over thousands of years you'd see maybe a doubling or quadrupling of it. Ie the median person in the year 500 AD lived rather similarly to the median person in the year 1500 AD.
When the industrial revolution rolled around, things changed. The estimate of GDP per capita increased faster than the population. People became richer and their lives became significantly better. This came with a substantial population increase, because people started living longer. The fruits of progress spread to poorer areas. The increase in food availability and medicine made many population counts skyrocket.
At some point during this it turned out that the richest areas started seeing a significant decrease in birthrates though. Why? I'm unsure. Perhaps people wanted better lives for their children and they couldn't afford to have as many children? Perhaps it wasn't necessary to have as many children anymore (social security)? Regardless what the reason is, birthrates have declined in developed countries. This allows us to plot a peak for the human population and decline afterwards. We don't need to worry about overpopulation anymore.
Will this pattern hold though? What if it turns out that when a society hits a GDP per capita of $500k of today's money that the birthrates start increasing again? 3% growth of GDP per capita plotted over 80 years would put US GDP per capita at $668k. What's the chance that there is no societal break point in the future that reverses the birthrate decline? Quite a few countries seem to be actively working on trying to find something like that.
I've typically heard two drivers:
1) children turned from an economic boon/necessity to a sink. They can start helping with farm work pretty early, not quite so much when the industry work, they have to be somewhat older and can't tag along when the parents are working.
2) women could spend their time working and earning money. They could start to support themselves.
We've been able to accelerate this trend by offering access to contraception and decreasing infant mortality.
That's a problem with school education. They give the wrong models. Exponential growth is impossible in nature because at some point it runs out of steam and fizzles out. Logistic curve or probit is a much better abstraction.
What actually happened is people in rich countries have plenty of food/water/shelter to continue reproducing... if they wanted to. The thing the models didn't account for is that people would choose to have fewer children based on standard of living.
To me it seems this had nothing to do with the standard limits of nature, but based on individuals' choices. Given those models' assumptions, I think they were valid. I would have made the same assumption based on past data as well.
[0] https://en.wikipedia.org/wiki/Projections_of_population_grow...
That might vary by culture, but I can't think of a time when I've seen it be stigmatized. I imagine that current generations chose to have less than 4 kids for economic and quality of life reasons, not because they see having many kids as somehow wrong.
* https://www.youtube.com/watch?v=FACK2knC08E
"Don’t Panic – The Facts About Population":
* https://www.gapminder.org/videos/dont-panic-the-facts-about-...
Whats strongly causative of the decline is literacy, especially women's literacy, and women's body autonomy and reproductive rights.
US opposition to WHO and to funding contraception and abortion is (thankfully) being counterbalanced by the gates foundations work, and other funding sources. A pox on the religious right, and American foreign policy.
And that's a good thing, right?
Link to the study can be found on the webpage.
Even more than economic growth is growth in standard of living, quality of life, health, and other things that population growth is now causing to decline, however much it helped before. Plenty of human populations have lived peacefully, stably, and abundantly without economic growth. Plenty have grown to overshoot and collapse.
In Thailand, for example, Mechai Viravaidya helped lead a nation go from 7 children per woman to below replacement level. Think the opposite of the One Child policy -- instead of forced abortions and sterilizations, all voluntary, fun teaching kids about condoms and making them available everywhere. It increased stability, peace, and abundance. Here's his TED talk: https://www.ted.com/talks/mechai_viravaidya_how_mr_condom_ma... "Thailand's 'Mr. Condom,' Mechai Viravaidya, retells the country's bold plan to raise its standard of living, starting in the 1970s. First step: population control. And that means a lot of frank, funny -- and very effective -- talk about condoms."
Baseline of 9.73 billion.
"China was forecasted to become the largest economy by 2035 but in the reference scenario, the USA was forecasted to once again become the largest economy in 2098"
That sounds like they they forecast war?
Also
"meeting the Sustainable Development Goals targets for education and contraceptive met need would result in a global population of 6·29 billion (4·82–8·73) in 2100"
Is the 2.4 billion people missing people a form of genocide or just good heath?
"Funding Bill & Melinda Gates Foundation."
Err why would you say this? You can read the report and it explains the falling fertility rate in China.
> Is the 2.4 billion people missing people a form of genocide or just good heath?
It's different projections based on different fertility rates.
That's an extraordinarily insulting claim to those who actually have suffered genocide.
It's important to help promote global community now, today when it matters.
And given how rich countries progress, extrapolation to poor countries make sense.
But it's not how it will go down, look at attempts 80 year ago what they thought 2020 would be
Not a great example, but it's well under -
https://www.ssa.gov/oact/NOTES/pdf_studies/study033.pdf
There are massive changes coming, and they won't be in the negative direction.
Longevity will mean increased fertility.
UBI means things other than money will matter, like it or not when jobs start decreasing.
Women biology cannot support birthing a child very well passed ~35. At 40yo heaving a child for a women becomes very hard.
So what good is increased longevity if biology prevents women from having more children at a later age.
I don't see how. We already live long enough to have a dozen kids per family. It's just that our society is structured such that raising kids is an expensive nightmare.
The paper says:
Role of the funding source The funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. All authors had full access to all the data in the study and had final responsibility for the decision to submit for publication.
> But it's not how it will go down, look at attempts 80 year ago what they thought 2020 would be
> Not a great example, but it's well under -
> https://www.ssa.gov/oact/NOTES/pdf_studies/study033.pdf
They estimated 2025 US population to be between 225M and 392M depending on the projection methodology used. The current population of the US is 328M, so this seems pretty good for an estimate 70 years ago!
> Longevity will mean increased fertility.
This would seem a bold claim. It hasn't anywhere in the world so far, and the correlation between increased longevity and decreased birthrates is very strong.
The Funders know how it'll come out.
Studies don't take into account the leaps that will happen because we don't know what they are. Things don't just continue as the previous 80 years. These jumps happened even when we didn't have the internet to super charge stuff.
> 2025 US population to be between 225M and 392M
That's 2050 in the document.
2020 is 210 - 305 million estimate. (pdf p29)
> decreased birthrates is very strong.
But not fertility. You won't be living to 120 without being a healthy and fertile 60 year old. It's fun to have work as number one for 20 years, but if it's easy to have kids in your 40's without IVF things will change.
> That's 2050 in the document.
Yes, you are right, my apologies.
2025 predictions are between 221M and 318M (table, page 16) which makes their "projection B" scenario almost exactly correct.
>2020 is 210 - 305 million estimate. (pdf p29)
Page 29 is a table called "Relative comparison of dependant and productive groups in the United States". There are no population numbers.
Page 25 has a graph which you maybe referring to. That doesn't have numbers, but they seem to be plotting the numbers from page 16.
> But not fertility. You won't be living to 120 without being a healthy and fertile 60 year old.
What evidence do you have of that? Increased life expectancy for women so far hasn't been matched by an increase in fertility beyond 40 years old.
You've said this with some certainty, were are you getting this from? This doesn't fit with all current data about general health and longevity, so I'd like to see who's saying this and what their case is.
The ovarian reserve only decreases from birth, so it becomes less and less likely for a woman to conceive as they get older.
https://en.wikipedia.org/wiki/Age_and_female_fertility also notes: A review in 2012 came to the result that therapeutic interventions to halt or reverse the process of reproductive ageing in women is limited, despite recent reports of the potential existence of stem cells which may be used to restore the ovarian reserve
https://en.wikipedia.org/wiki/Advanced_maternal_age has some further good reading on this.
There's two major forces that we could see UBI have when applied on a lifetime scale:
1) if citizens get it when they are born then having children could be economically rational again for some non trivial income bracket
2) if we actually do see more and more content unemployed citizens they could have the time and interest in having kids