[Ubirajara]

World historical and predicted populations (in millions)
Region 1750 1800 1850 1900 1950 1999 2008 2050 2100
World 791 978 1,262 1,650 2,521 5,978 6,707 8,909 >10,000
Africa 106 107 111 133 221 767 973 1,766 2,308
Asia 502 635 809 947 1,402 3,634 4,054 5,268 5,561
Europe 163 203 276 408 547 729 732 628 517
Latin America and the Caribbean16 24 38 74 167 511 577 809 912
Northern America 2 7 26 82 172 307 337 392 398
Oceania 2 2 2 6 13 30 34 46 51


World historical and predicted populations by percentage distribution
Region 1750 1800 1850 1900 1950 1999 2008 2050 2100
World 100 100 100 100 100 100 100 100 100
Africa 13.4 10.9 8.8 8.1 8.8 12.8 14.5 19.8 23.7
Asia 63.5 64.9 64.1 57.4 55.6 60.8 60.4 59.1 57.1
Europe 20.6 20.8 21.9 24.7 21.7 12.2 10.9 7.0 5.3
Latin America and the Caribbean2.0 2.5 3.0 4.5 6.6 8.5 8.6 9.1 9.4
Northern America 0.3 0.7 2.1 5.0 6.8 5.1 5.0 4.4 4.1
Oceania 0.3 0.2 0.2 0.4 0.5 0.5 0.5 0.5 0.5

http://en.wikipedia.org/wiki/World_Population

[Ubirajara]

Median age around the world:

[Ubirajara]

U.N. Forecasts 10.1 Billion People by Century’s End

The population of the world, long expected to stabilize just above 9 billion in the middle of the century, will instead keep growing and may hit 10.1 billion by the year 2100, the United Nations projected in a report released Tuesday. Growth in Africa remains so high that the population there could more than triple in this century, rising from today’s one billion to 3.6 billion, the report said — a sobering forecast for a continent already struggling to provide food and water for its people. The new report comes just ahead of a demographic milestone, with the world population expected to pass 7 billion in late October, only a dozen years after it surpassed 6 billion. Demographers called the new projections a reminder that a problem that helped define global politics in the 20th century, the population explosion, is far from solved in the 21st. “Every billion more people makes life more difficult for everybody — it’s as simple as that,” said John Bongaarts, a demographer at the Population Council, a research group in New York. “Is it the end of the world? No. Can we feed 10 billion people? Probably. But we obviously would be better off with a smaller population.” The projections were made by the United Nations population division, which has a track record of fairly accurate forecasts. In the new report, the division raised its forecast for the year 2050, estimating that the world would most likely have 9.3 billion people then, an increase of 156 million over the previous estimate for that year, published in 2008.
Among the factors behind the upward revisions is that fertility is not declining as rapidly as expected in some poor countries, and has shown a slight increase in many wealthier countries, including the United States, Britain and Denmark. The director of the United Nations population division, Hania Zlotnik, said the world’s fastest-growing countries, and the wealthy Western nations that help finance their development, face a choice about whether to renew their emphasis on programs that encourage family planning. Though they were a major focus of development policy in the 1970s and 1980s, such programs have stagnated in many countries, caught up in ideological battles over abortion, sex education and the role of women in society. Conservatives have attacked such programs as government meddling in private decisions, and in some countries, Catholic groups fought widespread availability of birth control. And some feminists called for less focus on population control and more on empowering women. Over the past decade, foreign aid to pay for contraceptives — $238 million in 2009 — has barely budged, according to United Nations estimates. The United States has long been the biggest donor, but the budget compromise in Congress last month cut international family planning programs by 5 percent. “The need has grown, but the availability of family planning services has not,” said Rachel Nugent, an economist at the Center for Global Development in Washington, a research group. Dr. Zlotnik said in an interview that the revised numbers were based on new forecasting methods and the latest demographic trends. But she cautioned that any forecast looking 90 years into the future comes with many caveats. That is particularly so for some fast-growing countries whose populations are projected to skyrocket over the next century. For instance, Yemen, a country whose population has quintupled since 1950, to 25 million, would see its numbers quadruple again, to 100 million, by century’s end, if the projections prove accurate. Yemen already depends on food imports and faces critical water shortages. In Nigeria, the most populous country in Africa, the report projects that population will rise from today’s 162 million to 730 million by 2100. Malawi, a country of 15 million today, could grow to 129 million, the report projected. The implicit, and possibly questionable, assumption behind these numbers is that food and water will be available for the billions yet unborn, and that potential catastrophes including climate change, wars or epidemics will not serve as a brake on population growth. “It is quite possible for several of these countries that are smallish and have fewer resources, these numbers are just not sustainable,” Dr. Zlotnik said. Well-designed programs can bring down growth rates even in the poorest countries. Provided with information and voluntary access to birth-control methods, women have chosen to have fewer children in societies as diverse as Bangladesh, Iran, Mexico, Sri Lanka and Thailand. One message from the new report is that the AIDS epidemic, devastating as it has been, has not been the demographic disaster that was once predicted. Prevalence estimates and projections for the human immunodeficiency virus made for Africa in the 1990s turned out to be too high, and in many populations, treatment with new drug regimens has cut the death rate from the disease. But the survival of millions of people with AIDS who would have died without treatment, and falling rates of infant and child mortality — both heartening trends — also mean that fertility rates for women need to fall faster to curb population growth, demographers said. Other factors have slowed change in Africa, experts said, including women’s lack of power in their relationships with men, traditions like early marriage and polygamy, and a dearth of political leadership. While about three-quarters of married American women use a modern contraceptive, the comparable proportions are a quarter of women in East Africa, one in 10 in West Africa, and a mere 7 percent in Central Africa, according to United Nations statistics. “West and Central Africa are the two big regions of the world where the fertility transition is happening, but at a snail’s pace,” said John F. May, a World Bank demographer. Some studies suggest that providing easy, affordable access to contraceptives is not always sufficient. A trial by Harvard researchers in Lusaka, Zambia, found that only when women had greater autonomy to decide whether to use contraceptives did they have significantly fewer children. Other studies have found that general education for girls plays a critical role, in that literate young women are more likely to understand that family size is a choice. The new report suggests that China, which has for decades enforced restrictive population policies, could soon enter the ranks of countries with declining populations, peaking at 1.4 billion in the next couple of decades, then falling to 941 million by 2100. The United States is growing faster than many rich countries, largely because of high immigration and higher fertility among Hispanic immigrants. The new report projects that the United States population will rise from today’s 311 million to 478 million by 2100.

http://www.nytimes.com/2011/05/04/wo...tion.html?_r=4

[Ubirajara]

The population boom has been particularly high in SSA Africa:

Congo:
2011 estimate 71,712,867 (19th)
1984 census 29,673,000

Nigeria (expected to be at around 730 million by 2100 according to the UN)
2010 estimate 155,215,573
1930 33,000,000

Ethiopia
2011 estimate 90,873,739
2007 census 73,918,505
1983 33,500,000

Angola (expected to hit over 47 million people by 2060)
2009 estimate 18,498,000
1970 5,600,000

Senegal:
2009 estimate 13,711,597
2002 census 9,967,21

Uganda:
2009 estimate 32,369,558 (37th)
2002 census 24,227,297

Mozambique:
2009 estimate 22,894,000
1990 14,200,000
1950 6,200,000

[Ubirajara]

Top 15 most populous countries in 2050:

1 India 1,736,226
2 China 1,393,942
3 United States 434,781
4 Nigeria 392,129
5 Indonesia 306,735
6 Pakistan 279,481
7 Brazil 237,890
8 Bangladesh 200,116
9 Philippines 158,331
10 Mexico 152,135
11 Democratic Republic of the Congo 149,327
12 Ethiopia 146,906
13 Tanzania 139,187
14 Russia 133,702
15 Egypt 126,929


Top 15 most populous countries in 2100

1 India 1,680,668
2 China 1,048,116
3 Nigeria 750,277
4 United States 530,331
5 Tanzania 324,946
6 Indonesia 282,221
7 Pakistan 279,746
8 Democratic Republic of the Congo 219,258
9 Brazil 200,943
10 Philippines 191,971
11 Uganda 176,309
12 Bangladesh 173,996
13 Kenya 166,076
14 Ethiopia 160,596
15 Iraq 151,979

http://esa.un.org/unpd/wpp/Excel-Data/population.htm

[Phil75231]

How did the UN calculate these projections? To me, it looks like mere extrapolation of present growth trends 90 years futureward. That doesn't sound like a very rational basis to me, particualarly for the present high-growth countries. Nigeria with 3/4 billion people by 2100? Tanzania with 324 million? I find that hard to believe given their relatively small land areas.

[Guaporense]

European countries will have a very small fraction of the world's population. That's rather strange, imagine the world where Euro has 5% of the population and Africa 23.7%! That's crazy.

Also, I doubt that the population boom of subsaaran africa will reach those numbers, if the region develops the natality rate will fall. If the region doesn't develop, they will not be able to feed the additional population.

[Sirrush]

I read a detailed paper that concluded that present population predictions are impossible. During the WWII period, politicians were already worrying about the low fertility... and then we had the baby boom!

Besides it's pretty obvious that, for example, Yemen can't sustain a population of 104,000,000 people when it already has trouble catering to the needs of a population of 23 million people, and with experts saying that Sanaa will be the first city to run out of water. To say that Africa's population is booming is one thing. To say that Tanzania will soon have a population equal to that of the present day USA is nonsense.

PS: Where is Bangladesh going to fit 70,000,000 more people in? Zoom in on any area of it on Google Earth and you'll see that it's practically all completely urbanised. That's like trying to stuff 2 elephants in a matchbox.

[Ubirajara]

By ELISABETH ROSENTHAL
Published: April 14, 2012

LAGOS, Nigeria — In a quarter-century, at the rate Nigeria is growing, 300 million people — a population about as big as that of the present-day United States — will live in a country roughly the size of Arizona, New Mexico and Nevada. In this commercial hub, where the area’s population has by some estimates nearly doubled over 15 years to 21 million, living standards for many are falling.

Last October, the United Nations announced the global population had breached seven billion and would expand rapidly for decades, taxing natural resources if countries cannot better manage the growth.

Nearly all of the increase is in sub-Saharan Africa, where the population rise far outstrips economic expansion. Of the roughly 20 countries where women average more than five children, almost all are in the region.

Elsewhere in the developing world, in Asia and Latin America, fertility rates have fallen sharply in recent generations and now resemble those in the United States — just above two children per woman. That transformation was driven in each country by a mix of educational and employment opportunities for women, access to contraception, urbanization and an evolving middle class. Whether similar forces will defuse the population bomb in sub-Sarahan Africa is unclear.

http://www.nytimes.com/2012/04/15/wo...anet.html?_r=4

[Ubirajara]

By ELISABETH ROSENTHAL
Published: April 14, 2012

LAGOS, Nigeria — In a quarter-century, at the rate Nigeria is growing, 300 million people — a population about as big as that of the present-day United States — will live in a country roughly the size of Arizona, New Mexico and Nevada. In this commercial hub, where the area’s population has by some estimates nearly doubled over 15 years to 21 million, living standards for many are falling.

Last October, the United Nations announced the global population had breached seven billion and would expand rapidly for decades, taxing natural resources if countries cannot better manage the growth.

Nearly all of the increase is in sub-Saharan Africa, where the population rise far outstrips economic expansion. Of the roughly 20 countries where women average more than five children, almost all are in the region.

Elsewhere in the developing world, in Asia and Latin America, fertility rates have fallen sharply in recent generations and now resemble those in the United States — just above two children per woman. That transformation was driven in each country by a mix of educational and employment opportunities for women, access to contraception, urbanization and an evolving middle class. Whether similar forces will defuse the population bomb in sub-Sarahan Africa is unclear.

http://www.nytimes.com/2012/04/15/wo...anet.html?_r=4