As worldwide population increases, resources become increasingly stretched and per capita income goes down (relative to the cost of living). This, in first world countries will probably result in a decline in the birthrate.
You only need to look towards CA to see where this is already happening. CA with it's excessive regulations has decreased the prosperity of it's people to the point of where it now has x3 times the number of poor people per capita than the national average (that's living cost adjusted ~ mostly due to housing cost and excessive energy costs and countless other regulations that increase living costs). I suspect this has played a roll in the decline of the birth rate in CA, now at the lowest its ever been since the great depression (it's been going down for the last 3 decades). As life becomes increasingly harsh, people have less babies - it's kinda hard to have a kid when your sharing a room in your parent's house, or live 6 to an apartment.
It's worth noting, the birth rate here in CA has been reducing for the last 30 years and recently has reached a 100 year low. It's currently lower than it was during the great depression.
I suspect that over the next few decades we will see the countries with the lowest birth rates start to push massive incentives for having more children.
The global economy runs on growth. If the population starts noticeably declining, it’ll take the economy down with it.
Poor people are still having a lot of kids, it's the developed world that has a problem. I think the decline is birthrate is much better explained by material wealth and the corresponding education of women that goes along with it as causes of the drop.
Nobody said anything about "stop having children" (good night!) - back to reality: I think the established pattern for countries joining the developed world is large economic growth/dev, followed by baby boom, followed by declining rates of reproduction until under the replacement value. This happens not only because of changing priorities of a wealthier population and changing behaviors, but also the availability of birth control and lower mortality rates (infant and elderly).
So it's not that birth rates decline "as their economy grows" - the birth rates go up during the growth phase - it's what comes after in an established prosperous society: fertility rates decrease.
It's consistent enough to predict with some certainty. As prosperity has grown worldwide, so global TFR has dropped. This happens one by one with the individual countries following a predictable pattern.
China does have regulatory limits that keep their TFR lower than it otherwise would be, they are still in their (modern) growth cycle. Absent that regulation, with the economic boom they've been seeing in last twenty years you'd expect to see the fertility rate boom accordingly, and while it appears to be growing despite the regulatory constraints, it's still below replacement value. This slow growth in the face of structural prosperity changes is the impact of regulation, not organic. https://www.macrotrends.net/countries/CHN/china/fertility-ra...
The birth rates seem to be declining in the developed countries, to the point where we might have to worry about underpopulation rather than overpopulation as the markets stop growing and the older part of the population begins to strain welfare systems.
Birth rates tend to stabilize in first world countries anyway. The only reason that isn't happening in the US is immigration--legal and otherwise. In Japan, the population is decreasing. In Europe, it's near zero growth in many countries.
It's a vicious cycle, but historically what we've seen is that drops in birth rate follows economic growth, not vice versa.
Poor economic conditions tends to mean parents rely on children for both work and for care in old age, and also correlates to lack of access to education on family planning as well as lack of access to contraceptives.
There are arguments to be made about precise cause and effect, but this pattern has been known for a long time; pretty much every developed country went through it, and almost all developing countries are on their way through the same pattern (almost all have seen birth rates drop dramatically, to the point the world is heading towards dropping population numbers within the next century).
>if the birth rate will start climbing due to COVID-19
Shifts in birth rates of developed countries are a drop in the ocean of global birth rates. "Developed" lives have a heavier ecological footprint, but it all pales in comparison to the shifts resulting from increased industrialisation of developing countries. Depressing demand for industrial goods and services (because of lockdown) is bound to have a much bigger impact than making a few kids more or less.
It's often observed that as societies grow richer, their birthrate plummets. The paradox is that in order to tap into those riches people have to work more, which may be one of the explanations for why the population tends to decline in those countries.
Thus the constraint may just be "time to make babies".
It's probably too much of a broad trend for that to be the case. As entire countries get wealthier, their birth rates drop: it's true in the US, Japan, Germany, Sweden, wherever. If you see a GDP per capita line going up, you will also see a birth rate line going down in nearly all cases. I suspect it's more likely something else: for example, access to and usage of birth control, access to other family planning controls, abortion, etc.
Edit: or even just access to entertainment that isn't "having sex." I remember a conversation with a (very) old woman who'd had many, many children; she said that... well, there wasn't much else to do back then...
However, people in many countries around the globe are having fewer children and not due to reaching "subsistence level". Some of the biggest impacts in birth rates are education, particularly for women, and birth control, both things are the product of technology raising living standards. Birth rates are not declining today because of Malthusian cycles.
You only need to look towards CA to see where this is already happening. CA with it's excessive regulations has decreased the prosperity of it's people to the point of where it now has x3 times the number of poor people per capita than the national average (that's living cost adjusted ~ mostly due to housing cost and excessive energy costs and countless other regulations that increase living costs). I suspect this has played a roll in the decline of the birth rate in CA, now at the lowest its ever been since the great depression (it's been going down for the last 3 decades). As life becomes increasingly harsh, people have less babies - it's kinda hard to have a kid when your sharing a room in your parent's house, or live 6 to an apartment.
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