[Patricius Maximus]

Originally Posted by old tired and angry

When I was born in the 1950s America had about 150 million people, now we have over 320 million. Because people are living longer and we are being flooded with immigrants who have larger families, America will have over 500 million people when my kids are my age. After that, who knows. The more people there is the more woman there is to have babies and population growth will build on an ever larger group of people. Compounding on it self until eventually we are going to be just like India and China with over a billion people.

The good news for me is I am old and will not have to face an America with a billion people, but my grandchild who was just born may see it, or his children may. What a scary thought.

Indeed. Personally I'd prefer the populations we had during the 19th century, when both Canada and the United States had about a tenth as many people - spread over the current population distribution that would make for two nicely-peopled countries with large tracts of lightly populated landscapes and true wilderness close to most people. Of course to have a 90% decrease (or any other change of such magnitude) in population takes a long time. As for myself I'd even settle for the population levels the world had in 1900 - to me they look a fair bit more pleasant than today's.

However, I doubt the U.S. will ever reach 1 billion or anywhere remotely close - birthrates settle to 1-2 children per woman, i.e. moderately below replacement, in almost every developed society including America. This is part of the demographic transition, something of a law in demography, and cannot be changed by any known method, so good or bad we'd better get used to it. 1-2 children per woman, all other things being equal, lead to the population shrinking - indeed, America's fertility rates have only hit replacement twice in the past 40 years, and without immigration you'd have a very slowly growing population (due to momentum) of 250 million. This isn't a very large difference from today; a more interesting exercise is to take out the Baby Boom, but I leave that up to the reader.

The other large factor aside from birth rates is migration. America historically had, in relative terms, an abundance of jobs and a shortage of people, and less-developed countries (19th century European periphery, 20th century Latin America) had, in relative terms, a shortage of jobs and an abundance of people. These are what are called push and pull factors in migration, and operate in the same way internationally as they do internally - the Rust Belt to Sun Belt migration had the same factors behind it. In America obviously the abundance of jobs depends on the economy - immigration is higher during good economies like the 1990s and the turn of the century, and is lower during bad economies like the 1930s and 2010s.

Where the immigrants come from and in what amount depends on the conditions in the immigrant-sending countries; as they become more developed, as they are all now and inevitably will continue to do, their supply of jobs within their own countries increases and their birth rates settle to the same level as America or Canada, greatly decreasing their population glut. The latter is especially the case in Latin America, where fertility rates for the most part are currently below replacement. With the sole exception of sub-Saharan Africa, the entire world is undergoing the same process, and even if there is a massive African immigration wave the base population of Africa won't be anywhere near what Latin America+Asia used to be at any point in the 21st century. So even an abundance of jobs in America won't attract other countries' excess population because soon there will be hardly any excess population (by historical standards) to attract.

Oh, in such a situation a few decades from now you'd still get immigrants coming in, but it'll be about as significant as today's flows from western and central Europe to America - noticeable, but not enough to make a large difference in how much the population grows. Because of this I wouldn't be surprised if America in 2100 had less people than it does today - the UN's low projection, which historically has been closer to the mark globally, puts US population at 304 million in 2100. Obviously over 84 years things could change drastically, so we'll see.

Economists tell us a rapidly growing population helps our economy. So when we have a billion people, everyone in America will be rich?

Literally the only economic indicator greater population helps is total GDP, which has no connection to living standards or wealth - at purchasing power parity America's and China's total GDPs are similar but since China has 4 times as many people the Chinese are only a quarter as wealthy. In turn the only thing total GDP helps is how much power the ruling class of such an economy can project on the world stage* - and that is all. That in turn has no influence whatsoever on the wealth or living standards of the people; of the CIA's list of top countries by GDP (PPP) per capita (the GDP metric relevant to actual people), most are small powers at best. So no, a large and/or growing population doesn't do anything for the economy. As a matter of fact there is a strong correlation - the larger the country the poorer it is, though this has less to do with total population and more to do with how it's divided between countries.

The underlying factors behind economic growth are the advance of technology and technique, increases in worker productivity, and new investment creating more wealth. Demographics have no effect on this, and its effect on the economy is small at best; the only supporting argument the population=wealth crowd has is Japan's horrible economic experience, but despite "much more favorable demographics" America's performance has been similar. We'll compare the per capita GDP growth of America and Japan, and then five other developed countries with demographics similar to Japan (low birth rates, stagnant or shrinking populations) over the 2000s:

United States - 1.46% (2000-05), 0.07% (2006-10)
Japan - 1.16% (2000-05), 0.46% (2006-10)
Latvia - 8.86% (2000-05), 0.44% (2006-10)
Lithuania - 8.33% (2000-05), 2.01% (2006-10)
Poland - 3.25% (2000-05), 4.71% (2006-10)
Czechia - 3.82% (2000-05), 2.15% (2006-10)
Estonia - 8.51% (2000-05), 0.16% (2006-10)

With the exception of Japan in the early 2000s all six of these "bad demographics" countries did better than America in the same time period - it's almost as if economic policy and the composition of a country's economy (and how different parts are affected by regional/global trends) dictate living standards rather than how high birth or immigration rates are. If you compare Western countries only, if anything it looks like very low birth rates are good for the economy. This actually makes a certain amount of sense, since living standards for the next generation will be optimized if energies are diverted from bearing and raising so many children and instead devoted to creating wealth the next generation will inherit, and advancing knowledge, technique, and technology to improve the productivity of the population's labors. Human welfare is also enhanced by freeing up more people's productive energies from managing their own children to strengthening other people's children. Living standards and human welfare may be best served by having a smaller number of healthier, stronger, and wealthier people (the K selection strategy) than a larger number of sicker, weaker, and poorer people (the r selection strategy). This holds true as long as you have a population large enough to be genetically viable (at most a few thousand) and to manage all the necessary aspects of a modern economy (at most a few hundred million).

*Which explains why the ruling class believe that population growth is good - what is really meant is that it's good for them, since greater population only helps their power. Jacking up total GDP for such purposes also neatly explains why our thought leaders, who usually gain from state power, believe it's best for women to work full-time and pump out lots of babies. Unfortunately for them real women, especially well-off white women, don't take well to that way of life, and most end up choosing one or the other; a minority find neither option optimal, such as those part-timers or homemakers who don't want any children. They are the GDP-pushers' worse nightmare and the whole notion is quite subversive today. That has nothing to do with living standards, though, since a person who goes out to work and uses his/her entire earnings to pay for domestic service generates much more GDP than a person who keeps house him/herself, even though it brings no net financial or quality of life gain to the household.

Originally Posted by beachmouse

This. It's not so much the raw numbers as the ratios of adults in the workforce to adults drawing a pension/retirement benefit of some sort. 4 working adults to one person drawing social security is a sustainable ratio; 2 workers for every retire, which is where many countries are headed, is not. So you can either try to grow the under 50 population of a country or declare a new retirement age of 75+ in order to get the ratios back to sustainability.

The dependency ratios are the relevant metric in as much as demographics affect the economy at all, but dependency ratios even in the least fecund countries are only set to revert to their historical norms as seen in the 19th century and earlier, only this time with the old as the dependent population instead of the young. A large dependent population of children didn't stop the late 19th century economy from posting some of the best per-capita growth rates ever recorded, and if anything old dependents are better than young dependents since older people have more time to accumulate wealth. The nature of the problem is not directly demographic, but financial. Current taxes paying current benefits like we have are unsustainable in shrinking populations, whereas current taxes paying current payers' future benefits are sustainable - the problem in transitioning is financial, where America needs a few trillion dollars of funding to pay for current beneficiaries (whose taxes were long ago spent) without doubling taxes on current payers. This is the "transition cost" problem which has vexed all reform efforts to date.

The idea floating around in the 1990s was that accumulated federal budget surpluses after the debt was paid off by 2010 would pay for the transition costs, and is the soundest idea I've heard to date. Obviously a frugal government is required to do that, and a booming economy helps* a great deal - instead since 2000 we saw a spendthrift government and an economy mired in depression. Now they have four times the debt to pay off and 16 years less time to accumulate surpluses. These problems are all financial and economic in nature; a country flush with wealth wouldn't have any problem financing almost any demographic situation.

*Although it isn't required. Even with the depressed economy and the tax cuts, if spending didn't grow any more than it did in the 1990s most of the past 16 years would have posted surpluses.

Except for the part where the baby boomers got to go to public universities when taxpayers in their state of residence paid 95% of the cost of instruction. The California-based boomers I know love to talk about how they got their degrees for $500 in fees a year. Then they graduated, decided their taxes were too high, and we've got the current system where the boomers' kids are seeing their own kids go off to college in a system where only about 30% of the cost of instruction in most states comes out of general fund pots, so those families are paying huge sums out of pocket for college compared to the boomers 'who got no funding' for college or whose presence required many school districts to build large numbers of schools to accomidate them, even if there were 30 kids in an elementary school classroom back then.

Again, this is primarily a financial problem - the amount of economic growth that could bring in greater revenues*, and the willingness of governments to allocate funds toward higher education instead of military, health, and welfare spending. What public colleges collect for their wildly-overpriced tuition (double what it was 10 years ago!) comes to about $70 billion per year; financing that amounts to less than the total cost of Obamacare ($100-200 billion a year), a third of the amount spent on Medicaid, or a tenth of the amount spent on the military, and scarcely more than the HUD budget. Even today if the federal government (Bernie Sanders included ) placed a higher value on higher education than other kinds of spending tuition-free college is well within its ability to pay for without raising taxes. If the economy were doing as well as the 1960s it would be even easier to pay for.

*Notice that during the period when Californian state colleges charged no tuition economic growth per capita was high.

Originally Posted by old tired and angry

The rapidly growing population of California sure is causing a boom??? Not really, the median income has dropped along with the huge growth in population. If rapid population growth brings a boom in the economy everyone in Phoenix, Las Vegas and Orlando must be millionaires by now!

California in 2010-15 was the 17th fastest-growing state, 5.1% compared to 4.1% for the country as a whole, and that's historically low for California; not exactly rapid growth, but California is a good example to use that simple population growth doesn't do squat for living standards. The fastest-growing states are generally doing well economically, but their migration-driven population growth is an effect of their good economies rather than a cause; people move there because of the better economy, not vice versa (now if only people would apply the same logic across national borders ). It's also worth noting that if it weren't for immigration and Latino birth rates California's population would be shrinking, and yet being able to "replenish the population" hasn't done squat for the people's situation.