It seems to me that the largest cost of an ageing population is medical. Not only are the old unable to work, but caring for them takes labor unavailable elsewhere. It is enough if we can keep the old healthy and we still get enormous benefits.

I don’t want to risk being too pedantic, but…..

“If the average woman only wants 2 kids anyway, it’s probably no big deal if she starts at 31 instead of 21″.

I’m not ready to buy this. Virtually all the EU
studies show that women generally ‘want’ 2 children. Over the reproductive cycle wish and reality don’t coincide. There are many reasons for this, and one of them is fertility which declines with age.

One book which has influenced my thinking on this a lot is: On Fertile Ground - A Natural History of
Reproduction by Harvard Anthropologist Peter Ellison.

Just one extract:

“Understanding the natural arc of female fecundity has come slowly and is as yet incomplete. But what we do know suggests that the relationship of age and female fecundity is a basic part of human biology, shaped by forces of natural selection that are both very old and possibly, on an evolutionary timescale, quite new……..

The most convincing evidence of age-specific changes in female fecundity comes from the realm of ‘assisted reproductive technologies’ or ART…. Age related declines in pregnancy rates have now been documented in virtually every ART procedure, including ovulation induction and in-vitro fertilization. Indeed, so common and well documented is the effect of female age
that it’s absence in any substantial database would be a significant, publishable finding” (pages 218-220).

Equally the measure of first child age is useful since it gives a rule of thumb measure of ‘family formation’ age, and this again has some significance for fertility.

One UN Demographer - John Bongaarts - has tried hard to use differences in this statistic (age at forming first family) to differentiate between North European and South European fertility: since North Europeans tend to leave home earlier, and form an ‘independent’ couple sooner.

“Actually, in Italy and Spain the rebound hasn’t gone nearly that far”.

No you are right. Bad wording on my part here. They are rebounding, but the impact is relatively small to date.

The important ongoing problem is how representative of one possible future the Italian and Spanish (and Greek and Portuguese) cases will turn out to be. A lot hangs on the rapidity of the decline from high fertility to below replacement.

Some years ago a demographer named Keyfitz introduced an idea which is actually quite important: population momentum.

Momentum gives an inherent ’snapshot’ of a country’s demography. The key distinction would be between stationary and stable population. It is possible to have a stationary (in numbers) ageing population where the pyramid is not stable (the US towards mid century may become like this). Or conversly a population where the fertility rate is stabilising but the momentum is still moving towards large population increases (the current case of many third world countries).

Now momentum equations have been used to show that a real problem can come if the drop in fertility happens too rapidly: in less than a reproductive generation.

This can produce a structural break and a very low
momentum figure which it may be difficult to climb
back from.

The old EU countries have had fertility declining over a relatively long time period, but the situation is accelerating with each new arrival below replacement.

“No, that’s too low.”

Yes, you’re right. But not much too low. According to the document (CDC National Vital Statistics Reports) you linked (for which thank you) the TFR for non-hispanic whites has been dropping from 1.866 in 2000 to 1.828 in 2002, whilst during the same period the Hispanic TFR has gone from 2.780 in 2000 to 2.718 in 2002.

The aggregate non-Hispanic black TFR’s hover around the national average 2.178 in 200, 2.047 in 2002.

Now part of the difficulty we may be having is about the definition of native/non native, and immigrant/non immigrant. Clearly second generation hispanic citizens are *non-immigrant*, but they are still under the impact of the migration process. Since it seems the vast majority of the hispanic population are post 1970 migrants or their descendents I maintain my view, whilst accepting the modification that immigration is
far from the only pertinent factor here.

In particular the discussion with Doug (Muir) has
brought home forcefully to me just how differently all
this will be perceived in the US, and how this
difference will only *add to the list of global
imbalances*.

Dave:

“There’s a fundamental difference between a literate
and an oral culture.”

Yes, this is a topic that has long interested me. I am
pretty much an ‘unrepentant McLuhanite’ on this
front. This interest also lead me at one stage to a
more or less obscurantist interest in the ‘authorship’
of the Odyssey and the Illiad.

But I’m making a bigger distinction here. In literate,
but pre ‘post-modern’ societies, grandparents have
played an important role in transmiting cultural
knowledge and experience to their grandchildren (again
depending on family structure, but this was clearly
true in Southern Europe eg). This link is now largely
broken, and the interesting question may be why, and
with what consequence: post coming on this in the near
future.

Your orginal point that immigration represents an
“enormous challenge particularly for nations that
define themselves along ethnic lines” is also
important though it hasn’t been taken up here. Clearly
the US, Canada, Australia and New Zealand are special
cases on a very large continuum.

Oliver:

“current economic woes is caused by demographics, is
the damage reversible and how long will it take?”

Difficult to say. My guess is that it is irreversible,
but that the impact can be reduced and that is what we
should be working on.

“political capital. What worries me is that
governments that fight a hard battle to allow
increased immigration will not raise retirement age or
curtail benefits.”

OK this is surely a real worry. Non of these measures
is popular. No easy answer here.

“Or should it better be spent on eg. Alzheimer
research?”

Two points here. In the first place advances in the
treatment of Alzheimer (desireable as they may be) may
not keep many people working longer, they will
probably help many people live longer with an
increased quality of life. ie in the near term it
seems unlikely that we will eliminate Alzheimer, we
may however slow down the deterioration. Secondly, in
general in this area it may be better to encourage the
private pharmaceutical industry to shoulder the cost.

Couple of points here.

Apart from the statistical component, it is important to bear in mind that the rise in childbearing age has a biological component: the older the woman the less fertile (basically).

In rich, post-demographic transition countries, this effect is pretty secondary. If the average woman only wants 2 kids anyway, it’s probably no big deal if she starts at 31 instead of 21.

Frex, in the US — and especially in the Northeast — teenage births have been dropping for the last couple of decades. Meanwhile births to women over 30 have been rising at a rate of about 3% per year, doubling since the early ’80s:

And also there is a strong social component of what we could call ‘couple instability’ as you move up in the thirties age group: ie people separate more.

It’s a lot more complicated than that, especially if you’re looking at people with kids. Short version: in the US, at least, divorce rates drop smoothly with age of first marriage.

Immigrants on arrival tend to be clustered in the 20 - 40 age range, which means you give an automatic boost to women in the childbearing age. This then obviously has an impact on TFR.

Secondly migrants tend to come from cultures where age at first child is *lower*, and where the number of anticipated children per family tends to be slightly higher.

Yeah, but this is not the main reason for higher USAn TFRs and birthrates. It helps, yes, but it’s secondary. Mexicans make up the biggest immigrant group in the US, and Mexican-American family patterns converge rapidly on USAn norms, becoming almost indistinguishable by the second native-born generation. The fertility boost thus comes only from the immigrants themselves and their children.

Since the US Census tracks data by race and state, it’s also possible to tease out some interesting data bits. So, for instance, white non-Hispanic Texans have a TFR of 2.13: they’d be well over replacement rate even without immigrants or their children.

A further piece of evidence might be that in the 70’s US TFR’s were dropping below replacement rates just like all other OECD countries, and that it is only after 1988 that levels have climbed back up again

Yeah, but US rates never dropped as low as European or Japanese.

Now in the US you also keep data on ethnic identities, which enables you to break the numbers down a bit. For example I have seen numbers for ‘Anglo’ TFRs which are around 1.7

No, that’s too low. You want to look at National Vital Statistics Reports, Vol. 52, No. 19 (5/10/2004)

http://www.cdc.gov/nchs/data/nvsr/nvsr52/nvsr52_19.pdf

Averaged data over three years, from 2000 to 2003.

For a detailed look at one state, with projections:

http://txsdc.utsa.edu/tpepp/2004projections/2004_txpopprj_txtotnum.php

– scroll down and stare at the “0.0″ scenario, which assumes the state sealing its borders to all immigrants. White and black (native) populations continue to grow slowly; Hispanics grow quickly at first, then slow down to native growth rates. The population as a whole grows by about 30% by 2040.

I’m not up to date on country of origin data for recent US migration, but I suspect Mexico is slowing down

Actually, not. But that’s another story.

Incidentally, it would be interesting to see a study on distribution of TFRs and immigration: as an outsider I have the impression that New England may have received relatively less immigration from the south, whilst in the case of Arizona and (certainly) Texas this could be important.

It gets complicated. Short version:

New England — very “advanced” native demographics, with late marriages, late first births, and small families. Not much immigration. Result: declining TFRs, low birth rates, low or zero population growth. (Although note that New England overall has a TFR around 1.70, which is still higher than most countries in Europe.)

Mid-Atlantic (New York, New Jersey) — advanced demographics, though not as much as New England. Lots of immigration. Native population growing slowly or not at all, but decent growth from immigration.

The South — less advanced demographics… earlier marriages, earlier first births (and more divorces). Very little immigration outside of Florida. Most Southern states have modest growth rates, almost entirely driven by native growth and TFRs around 2.1 - 2.2.

The Southwest — even less advanced demographics (partly a product of _internal_ immigration, which is yet another story) plus lots of immigration. Result: growth at a rate more typical of the Third World than the First. Arizona, for instance, went from 750,000 people in 1950 to 5.1 million in 2000, and is projected to have 8.2 million by 2020. Texas’ population has nearly doubled since 1970, and is expected to double again by 2040.

Utah is surprising, but since I know relatively little about Utah (not to say next to nothing) I cannot say anything useful.

Mormons.

California also - unsurprisingly - seems to be experiencing a ‘relative boom’ in fertility.

No, actually California looks more like New York — advanced native demographics, lots of immigrants. The greater growth rate comes from internal immigration: people moving to CA from Kansas, more or less.

You are undoubtedly right: falling fertility has two components, less absolute numbers of children per women, and later age at first child.

Later age for all children, to nitpick.

What does this mean: that the initial rapid rise in age at first child sends the numbers plummeting: to the 1.2 TFRs seen in Italy and Spain. These numbers are artificially low, and there is then a ‘rebound’ but only up to around 1.7.

Actually, in Italy and Spain the rebound hasn’t gone nearly that far. They really aren’t having kids.

In France, OTOH, it looks like they’re going to stabilize at a TFR around 2.2 for a while.

Without immigration (and repeat, for cultural reasons migrants may have the first child earlier) it is extraordinarily difficult to get much above this level.

Which loops us back to my original point: the US has managed it, even taking out immigrants /and/ the first generation of immigrants’ kids. Native born USAns are replacing themselves.

What makes the US different from all other advanced countries is a separate, fascinating question.

Doug M.

what else is there that would make the US relatively unique?
Population density, a relatively unbroken history of prosperity, frequent foreign wars, size

At the same time the US pyramid still looks decidedly wobbly:

http://www.un.org/esa/population/publications/migration/usa.pdf

And it is, of course, important to remember that the changing dependency ratios are a result of two processes, declining fertility and increasing life expectancy. The US is going to be affected by this latter component just like all the rest.

“Establishing a retirement age may be equal but it has disparate impact”.

I accept the force of this point, but this just complicates things further.

“Don’t downplay cultural constructs, either.”

No, I don’t and I hope you haven’t given that impression. In the OECD world since 68 we have probably had an increasingly ‘young’ oriented society: this may well be about to change. Certainly there will be plenty of money to be made out of catering for the needs of old people. These are demand-related items, which here I have been deliberately leaving top one side.

One thing does worry me though: in China, and in earlier times in Europe older people were respected. In part this was because they were relatively few in number, and because their experience was seen as having value. My worry is that now there will be many more, and that maintaining them (us) will be very costly, and (and this is a separate argument for another post), with an increased rate of technological and social change meaning that the accumulated experience has less apparent value, well my worry is that social attitudes towards the elderly could become very negative indeed in some sections of the population.

“In the short run, probably health care”

But then I don’t see how fleshing out the pyramid will be a downside now. Obviously 30 years out going forward more population now will mean increased health costs later. What I am worried about is relatively short term buckling of the financial system under the weight of inverting the pyramid too rapidly.

“But what makes you think that there is a steady state of population in an industrialized society.”

This is just a guess. There is no way we can know this, I’m suggesting that things may achieve a new steady state, not that they have to, and I am suggesting that this would appear to be at least a century away due to inbuilt momentum globally going forward.

I know it is probably only a case of you using a convenient shorthand, but obviously we won’t be talking about an ‘industrial society’. Industry is already responsible for less than 30% of GDP in most of our economies. What I’d like to do is strip out reference to any particular set of social arrangements and look at this on a very abstract - species/environment - level. In this case either we could move on a continuing ‘boom-bust’ cycle, like we’ve had over the last 300 years, or things could start to steady themselves up. My guess is that the latter could happen, but it is only that, a guess. And in any event we most likely won’t be around to see :).

In the short run, probably health care.
And I wouldn’t limit this to a decade. It’ll be there for at least 30 years. But what makes you think that there is a steady state of population in an industrialized society? For all we have hard evidence, the natural state of such a population may be fluctuating.