New model shows dramatic global decline in ratio of workers to retired people

August 20, 2012, University of Washington

A new statistical model predicts that by 2100 the number of people older than 85 worldwide will increase more than previously estimated, and there will be fewer working-age adults to support them than previously expected.

The findings, reported by researchers at the University of Washington and the United Nations, suggest an even greater decrease in the coming decades in support for social security programs for elderly adults.

Lead author Adrian Raftery, UW professor of statistics and sociology, was surprised by how dramatically the proportion of the world's "oldest old" will increase by the end of the century.

"This has been studied a lot in developed countries, but what we see with this is that the increase in people over 85 will be a worldwide phenomenon," he said.

The study will be published Aug. 20 in the online early edition of the .

In China, the world's most-populous country, the number of working-age adults for each person 65 or older will shrink from 7.9 in 2010 to 1.6 in 2100. The ratio in India, the world's second-most-populous country, will decrease from 11.1 in 2010 to 2.0 in 2100.

The ' ratio declines from 4.6 in 2010 to 1.8 by the end of the century. Other developed nations with low fertility rates show somewhat larger declines, including the Netherlands dropping from 4.0 to 1.6 and the United Kingdom dropping from 3.6 to 1.6 by century's end.

"The United States has more favorable numbers than other developed countries now, and will retain a slight advantage over other countries at the end of the century," Raftery said. He attributes the United States' relatively more-promising outlook to the country's higher levels of new births and to immigration.

The researchers did not produce predictions for the 38 countries with generalized HIV/AIDS epidemics, because those nations require a different .

Standard population projection methods yield just one estimate without giving a sense of wiggle room. In contrast, Raftery and his co-authors developed a Bayesian statistical approach that produces a low and high estimate for each country's population as well as the likelihood that the actual population will fall in that range. The method makes population predictions based on countries' previous fertility and mortality rates and immigration patterns.

This probabilistic strategy allows policy-makers to make better-informed decisions, such as determining whether to build new schools.

"We don't know for sure what will happen in the future, but this model gives us a better sense of the accuracy of the projections," Raftery said.

Raftery hopes to use the model to help the United Nations make its 2012 prediction of world population growth, which will be released in February 2013.

Previously, he used a similar with the ' 2010 population prediction. That model projected a world population of 10.1 billion by 2100, which is 1 billion more than previously thought.

Explore further: How many will we be? Are population estimates off the mark?

More information: “Bayesian probabilistic population projections for all countries,” by Adrian E. Raftery, Nan Li, Hana Sevcikova, Patrick Gerland, and Gerhard K. Heilig, PNAS.

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2.3 / 5 (3) Aug 20, 2012
Well, either todays people need to seriously get to work on another baby boom (like the one after world war II) or more needs to be spent on medical research so as to keep people working till they're 80 at a reasonable cost. ;P
4 / 5 (2) Aug 20, 2012
Automation would gradually make human workers more and more obsolete. Thats why I am not afraid of such predictions. Productivity could rise even when the number of human workers would fall.
3 / 5 (2) Aug 20, 2012
We should choose whether to stop the population explosion or whether to face the generation crisis. I do prefer the first one - at the moment, when the population will stabilize, the generation crisis will solve itself automatically.
3.4 / 5 (5) Aug 20, 2012
At worst, adults will be required to be corporate wage slaves for a longer period.
5 / 5 (3) Aug 20, 2012
The future of society makes for some strange thought experiments.

If the future supports long life but not particularly productive lives, then there will indeed be trouble. Especially as ever increasing amounts of resources are devoted to services and away from productivity.

If Long life can also be paired with productivity, the general picture improves. But wealth concentration and meaningful employment for everyone will become greater challenges.
3 / 5 (4) Aug 20, 2012
Human beings must strive to remain productive while they exist. Things don't make sense any other way.

This whole "retirement" idea... I don't know.
Aug 20, 2012
This comment has been removed by a moderator.
3 / 5 (3) Aug 20, 2012
There is a critical point approaching in human history. The wealthy are continuing to gain control of the means of production, around the world. Production is being automated at an increasing rate.
Sooner or later, ordinary people are going to find that they are not needed.. and not wanted... by those in power.
This doesn't apply just to the old and infirm... it applies to everyone who currently works for a living... or wants to.
Good luck to us!
1 / 5 (2) Aug 21, 2012
Soylent Green.
5 / 5 (1) Aug 21, 2012
I like their work, but it does not take into account growth of very fertile minoritie and consious changes in child policies.

Fertility rates of religious people seem to be consistently higher compared to non-religous people and in the end the whole society may be made up by fertile religious minorities. Or not.. But it is a possibility at any rate. The authors do not seem to have accounted for different fertility rates of different population strata.

Also, what would happen if the government would set income tax for all families with three or more children to zero? Extreme, yes, but I think that we can all see that fertility rates in the developed world is closely linked to the echonomic terms. Surely the baysian model cannot take drastic policy changes into consideration?
3 / 5 (4) Aug 21, 2012
Since 80 to 90 percent of all labor is entirely unproductive or even anti-productive, you need to define what you mean by "productive".

"Human beings must strive to remain productive while they exist." - Zippy
5 / 5 (2) Aug 21, 2012
Decentralised/personal energy production and decentralised/ersonal manufacturing (i.e. where everyone can manufacture anything they personally need from raw materials).
If we can get that to work then we won't need to fear having lots of people around who cannot work.
OK, it would be the end of the money/capitalism system as we know it - but seriously: if you could have whatever you want without slaving 9-to-5 - wouldn't you think it worth it?
1 / 5 (1) Sep 10, 2012
Since 80 to 90 percent of all labor is entirely unproductive or even anti-productive....

You would know all about this, no doubt... :)
not rated yet Sep 11, 2012
Since 80 to 90 percent of all labor is entirely unproductive or even anti-productive, you need to define what you mean by "productive".

"Human beings must strive to remain productive while they exist." - Zippy

You must lead a very spare life.
2.3 / 5 (3) Sep 11, 2012
We can always hope and pray the Mormons, Muslims, Catholics and Evangelicals will continue to be fruitful and multiply.

Just goes to show how the state kills.
Govt mandated retirement schemes 'free' people from having to depend upon their children to support them so why bother with children.
'Progressives' may win battles but they lose the war.
2.3 / 5 (3) Sep 11, 2012
How can childless, atheist pensioners accept being supported by breeding religionists?
5 / 5 (1) Sep 11, 2012
How can childless, atheist pensioners accept being supported by breeding religionists?

Oh, don't start that crap now, please...
3 / 5 (2) Sep 11, 2012
"You would know all about this, no doubt... :)" - Zippy

I do.

You don't actually think that that cheap steel muffler sitting under your car was designed to last do you?

It was designed to provide suckers with a reason to purchase another one.

It keeps the wage slaves occupied and keeps the invisible hand of the corporation emptying their wallet.
not rated yet Sep 12, 2012
How can childless, atheist pensioners accept being supported by breeding religionists?

Because that pensioner has worked all his life and has contributed to society? Contributions that the younger generation can enjoy? What the hell has support of the elderly in a society got to do with whether you believe or not? It's just a form of decency (and common sense) to do so.
3 / 5 (2) Sep 12, 2012
How can childless, atheist pensioners accept being supported by breeding religionists?

Oh, don't start that crap now, please...

It is the truth. The only people with high fertility rates are religious.
Since most pension plans are Ponzi schemes, current workers must pay for those not working.
Of course all of this could change IFF pension plans were real trust funds growing with a growing economy.
But 'progressives' will have none of that.

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