Information about World Population

The world population is the total number of humans on Earth at a given time. In September 2007, the world's population is believed to have reached over 6.6 billion. In line with population projections, this figure continues to grow at rates that were unprecedented before the 20th century, although the rate of increase has almost halved since its peak, which was reached in 1963, of 2.2 percent per year. The world's population is expected to reach over 9 billion by the year 2050.

Population figures

Below is a table with historical and predicted population figures shown in millions.^[1][2][3] The availability of historical population figures varies by region. Please see World population estimates for more figures.

World historical and predicted populations^[4]

Region	1750	1800	1850	1900	1950	1999	2050	2150
World	791	978	1,262	1,650	2,521	5,978	8,909	9,746
Africa	106	107	111	133	221	767	1,766	2,308
Asia	502	635	809	947	1,402	3,634	5,268	5,561
Europe	163	203	276	408	547	729	628	517
Latin America and the Caribbean	16	24	38	74	167	511	809	912
Northern America	2	7	26	82	172	307	392	398 !Oceania |2||2||2||6||13||30||46||51

World historical and predicted populations by percentage distribution

Region	1750	1800	1850	1900	1950	1999	2050	2150
World	100	100	100	100	100	100	100	100
Africa	13.4	10.9	8.8	8.1	8.8	12.8	19.8	23.7
Asia	63.5	64.9	64.1	57.4	55.6	60.8	59.1	57.1
Europe	20.6	20.8	21.9	24.7	21.7	12.2	7.0	5.3
Latin America and the Caribbean	2.0	2.5	3.0	4.5	6.6	8.5	9.1	9.4
Northern America	0.3	0.7	2.1	5.0	6.8	5.1	4.4	4.1 !Oceania |0.3||0.2||0.2||0.4||0.5||0.5||0.5||0.5

Estimated world population at various dates, in thousands

Year	World	Africa	Asia	Europe	Latin America	Northern America*	Oceania	Notes
-8000	5 000**							[5]
-1000	50 000							[5]
-500	100 000							[5]
1	200,000+							[6]
1000	310 000
1750	791 000	106 000	502 000	163 000	16 000	2 000	2 000
1800	978 000	107 000	635 000	203 000	24 000	7 000	2 000
1850	1 262 000	111 000	809 000	276 000	38 000	26 000	2 000
1900	1 650 000	133 000	947 000	408 000	74 000	82 000	6 000
1950	2 518 629	221 214	1 398 488	547 403	167 097	171 616	12 812
1955	2 755 823	246 746	1 541 947	575 184	190 797	186 884	14 265
1960	2 981 659	277 398	1 674 336	601 401	209 303	204 152	15 888
1965	3 334 874	313 744	1 899 424	634 026	250 452	219 570	17 657
1970	3 692 492	357 283	2 143 118	655 855	284 856	231 937	19 443
1975	4 068 109	408 160	2 397 512	675 542	321 906	243 425	21 564
1980	4 434 682	469 618	2 632 335	692 431	361 401	256 068	22 828
1985	4 830 979	541 814	2 887 552	706 009	401 469	269 456	24 678
1990	5 263 593	622 443	3 167 807	721 582	441 525	283 549	26 687
1995	5 674 380	707 462	3 430 052	727 405	481 099	299 438	28 924
2000	6 070 581	795 671	3 679 737	727 986	520 229	315 915	31 043
2005	6 453 628	887 964	3 917 508	724 722	558 281	332 156	32 998**

* Northern America indicates the United States and Canada.

** This figure is disputed.

Rate of increase

Main article: Population growth

Different regions have different rates of population growth, but in the 20th century, the world saw the biggest increase in its population in human history due to medical advances and massive increase in agricultural productivity made by the Green Revolution.

In 2000, the United Nations estimated that the world's population was then growing at the rate of 1.14% (or about 75 million people) per year^[7]. According to data from the CIA's 2005–2006 World Factbooks, the world human population currently increases by 203,800 every day.^[8] The 2007 CIA factbook increased this to 211,090 people every day.

Globally, the population growth rate has been steadily declining from its peak of 2.19% in 1963, but growth remains high in the Middle East and Sub-Saharan Africa.^[9]

In some countries there is negative population growth (ie. net decrease in population over time), especially in Central and Eastern Europe (mainly due to low fertility rates) and Southern Africa (due to the high number of HIV-related deaths). Within the next decade, Japan and some countries in Western Europe are also expected to encounter negative population growth due to sub-replacement fertility rates.

Population growth which exceeds the carrying capacity of an area or environment results in overpopulation. Conversely, such areas may be considered "underpopulated" if the population is not large enough to maintain an economic system.

Population (est.) 10,000 BC – 2000 AD.	Population (est.) in log y scale	World population 1950–2000	Increase rate 1950–2000

Milestones

The following shows estimates of when each billion milestone was or will be met:

Population	1 billion	2 billion	3 billion	4 billion	5 billion	6 billion	7 billion	8 billion	9 billion
Year	1804	1927	1961	1974	1987	1999	2011	2024	2042
Years until next billion	123	34	13	13	12	12	13	18

These numbers show that the world's population has tripled in 72 years, and doubled in 38 years up to the year 1999. Including some more estimates, the world population has been doubled or will double in the following years (with two different starting points). Note how, during the 2nd millennium, each doubling has taken roughly half as long as the previous doubling.

Population	250 million	500 million	1 billion	2 billion	4 billion	8 billion
Year	AD 950'''	1600	1804	1927	1974	2024
Years until next doubling	650	204	123	47	50

Population	. . .	375 million	750 million	1.5 billion	3 billion	6 billion
Year		1420	1720	1875	1961	1999
Years until next doubling		300	155	86	38

Population distribution

Asia accounts for over 60% of the world population with almost 3.8 billion people. China and India alone comprise 20% and 16% respectively. Africa follows with 840 million people, 12% of the world population. Europe's 710 million people make up 11% of the world's population. North America is home to 514 million (8%), and South America to 371 million (5.3%).

The 15 most populous nations

From DSW-Datareport 2006 ("Deutsche Stiftung Weltbevölkerung"):

1. China: 1.32 billion (about 20% of world population)
2. India: 1.12 billion (about 17%)
3. United States: 300 million (about 4.6%)
4. Indonesia: 225 million (about 3.5%)
5. Brazil: 186 million (about 2.8%)
6. Pakistan: 165 million (about 2.5%)
7. Bangladesh: 147 million (about 2.3%)
8. Russia: 143 million (about 2.2%)
9. Nigeria: 135 million (about 2.1%)
10. Japan: 128 million (about 2.0%)
11. Mexico: 108 million (about 1.7%)
12. Philippines: 86 million (about 1.3%)
13. Vietnam: 84 million (about 1.3%)
14. Germany: 82 million (about 1.3%)
15. Egypt: 75 million (about 1.2%)
16. Ethiopia: 75 million (about 1.2%)
17. Turkey: 73 million (about 1.2%)

Approximately 4.4 billion people live in these 17 countries, representing roughly two-thirds of the world's population. If added together, all nations in the European Union, with 494 million people - about 7.3% of world's population in 2006 - would be third in the list above.

Demographics of youth

According to the 2006 CIA World Factbook, around 27% of the world's population is below 15 years of age.^[10]

Before adding mortality rates, the 1990s saw the greatest number of raw births worldwide, especially in the years after 1995, despite the fact that the birth rate was not as high as in the 1960s. In fact, because of the 160 million-per-year raw births after 1995, the time it took to reach the next billion reached its fastest pace (only 12 years), as world population reached 6 billion people in 1999, when at the beginning of the decade, the reaching was designated for the year 2000, by most demographers. People aged 7 through 17 make up these births, today.

1985–1990 marked the period with the fastest yearly population change in world history. Even though the early 1960s had a greater growth rate than in the mid and late 1980s, the population change hovered around 83 million people in the five-year period, with an all-time growth change of nearly 88 million in 1990. The reason is because the world's population was greater in the mid and late 1980s (around 5 billion) than in the early 1960s (around 3 billion), which meant that the growth rate in the 1980s was no factor on the dramatic population change. People aged 17 to 22 make up these births, today.

Forecast of world population

''See also: UN population projections

The future of world population could be significantly affected by the worldwide HIV/AIDS pandemic. But if HIV/AIDS is controlled or eradicated, world population could increase much faster than predicted.

In the long run, the future population growth of the world is difficult to predict. Birth rates are declining slightly on average, but vary greatly between developed countries (where birth rates are often at or below replacement levels), developing countries, and different ethnicities. Death rates can change unexpectedly due to disease, wars and catastrophes, or advances in medicine. The UN itself has issued multiple projections of future world population, based on different assumptions. Over the last 10 years, the UN had consistently revised these projections downward, until the 2006 revision issued March 14, 2007 revised the 2050 mid range estimate upwards by 273 million.

Alternately, the United States Census Bureau issued a revised forecast for world population that increased its projection for the year 2050 to above 9.4 billion people (which was the UN's 1996 projection for 2050), up from 9.1 billion people. The latest Census Bureau estimates for the same upcoming years are as follows:^[11]

Year	Population (in billions)
2010	6.8
2020	7.6
2030	8.3
2040	8.9
2050	9.4

Other projections of population growth predict that the world's population will eventually crest, though it is uncertain exactly when or how. In some scenarios, the population will crest as early as the mid-21st century at under 9 billion, due to gradually decreasing birth rates, (the "low variant" of <ref name="unpp" />), The "high variant" from the same source gives a population between 10 and 11 billion in 2050.

In other scenarios, disasters triggered by the growing population's demand for scarce resources will eventually lead to a sudden population crash, or even a Malthusian catastrophe (also see overpopulation).

Below is a table of predicted population figures.<ref name="unpp" />^[12][13] Please see World population estimates for more figures.

Year	World	Africa	Asia	Europe	Latin America	Northern America*	Oceania
2010	6 830 283 000 (100%)	984 225 000 (14.4%)	4 148 948 000 (60.7%)	719 714 000 (10.5%)	594 436 000 (8.7%)	348 139 000 (5.1%)	34 821 000 (0.5%)
2015	7 197 247 000 (100%)	1 084 540 000 (15.1%)	4 370 522 000 (60.7%)	713 402 000  (9.9%)	628 260 000 (8.7%)	363 953 000 (5.1%)	36 569 000 (0.5%)
2020	7 540 237 000 (100%)	1 187 584 000 (15.7%)	4 570 131 000 (60.6%)	705 410 000  (9.4%)	659 248 000 (8.7%)	379 589 000 (5.0%)	38 275 000 (0.5%)
2025	7 851 455 000 (100%)	1 292 085 000 (16.5%)	4 742 232 000 (60.4%)	696 036 000  (8.9%)	686 857 000 (8.7%)	394 312 000 (5.0%)	39 933 000 (0.5%)
2030	8 130 149 000 (100%)	1 398 004 000 (17.2%)	4 886 647 000 (60.1%)	685 440 000  (8.4%)	711 058 000 (8.7%)	407 532 000 (5.0%)	41 468 000 (0.5%)
2035	8 378 184 000 (100%)	1 504 179 000 (18.0%)	5 006 700 000 (59.8%)	673 638 000  (8.0%)	731 591 000 (8.7%)	419 273 000 (5.0%)	42 803 000 (0.5%)
2040	8 593 591 000 (100%)	1 608 329 000 (18.7%)	5 103 021 000 (59.4%)	660 645 000  (8.0%)	747 953 000 (8.7%)	429 706 000 (5.0%)	43 938 000 (0.5%)
2045	8 774 394 000 (100%)	1 708 407 000 (19.5%)	5 175 311 000 (59.0%)	646 630 000  (7.4%)	759 955 000 (8.7%)	439 163 000 (5.0%)	44 929 000 (0.5%)
2050	8 918 724 000 (100%)	1 803 298 000 (20.2%)	5 217 202 000 (58.5%)	653 323 000  (7.3%)	767 685 000 (8.6%)	447 931 000 (5.0%)	45 815 000 (0.5%)

* Northern America indicates the United States and Canada

Predictions based on our growing population

In 1798, Thomas Malthus incorrectly predicted that population growth would eventually outrun food supply in the middle of the 19th century, resulting in catastrophe. In 1968, Paul R. Ehrlich reignited this argument with his book The Population Bomb, which helped give the issue significant attention throughout the 1960s and 1970s. The dire predictions of Ehrlich and other neo-Malthusians were vigorously challenged by a number of economists, notably Julian Simon.

On the opposite end of the spectrum there are a number of people who argue that today's low fertility rates in Europe, North America and Australia, combined with mass immigration, will have severe negative consequences for these countries.^[14]

Child poverty has been linked to people having children before they have the means to care for them.^[15] More recently, some scholars have put forward the Doomsday argument applying Bayesian probability to world population to argue that the end of humanity will come sooner than we usually think.^[16]

It should be noted that between 1950 and 1984, as the Green Revolution transformed agriculture around the globe, world grain production increased by 250%. The energy for the Green Revolution was provided by fossil fuels in the form of fertilizers (natural gas), pesticides (oil), and hydrocarbon fueled irrigation.^[17] The peaking of world hydrocarbon production (Peak oil) may test Malthus and Ehrlich critics.^[18]

The world population has grown by about four billion since the beginning of the Green Revolution and most believe that, without the Revolution, there would be greater famine and malnutrition than the UN presently documents (approximately 850 million people suffering from chronic malnutrition in 2005).^[19]

Number of humans that have ever lived

Estimates of the number of human beings who have ever lived on Earth constitute an extremely large range, with low estimates around 45 billion, and the highest estimates topping out around 125 billion. Many of the more robust estimates fall into the range of 90 to 110 billion humans.

It is impossible to make anything approaching a precise count of the number of human beings who have ever lived, for the following reasons:

• The specific range of characteristics, physiological, psychological and cultural, which define a human being, continue to be a subject of intense scholarly research and debate. It is thus not possible to know just when in human evolutionary history to begin the count. Resolving these debates would require drawing a thin line between early humans and pre-humans, and in the lack of anthropological evidence, the placing of such a line is shaped by the academic position and interpretation of experts and remains arbitrary at best.
• Even if the scientific community reached wide consensus regarding what characteristics defined the very first human beings, it would be nearly impossible to pinpoint the exact decade, century, or millennium when they first appeared. The fossil record is simply too scarce. Only a few thousand fossils of early humans have ever been found, most no bigger than a tooth or a knucklebone. While that may sound like a large number, it is truly minuscule when you consider that these few thousand bone fragments must be used to extrapolate the population distribution of millions of early human beings spread thinly across the face of the Earth.
• Until the late 1700s, exceedingly few nations, kingdoms, or empires had ever performed a census that was considered to be anything more than a rough estimate. In many of these early attempts, the focus was not even on counting people, but merely a subset of the people for purposes of taxation or military service. Even with the advent of agencies like the United States Bureau of the Census, reliable census methods and technologies continue to evolve right into the twenty-first century. Even today, these reliable methods and technologies are not applied uniformly in all parts of the world. In short it has been less than two centuries that we have had anything that remotely resembles the robust statistical data that would be needed to perform a calculation regarding the total number of humans that have ever lived.

Considering the relatively small population in the early phases of human development, the first two factors are likely to be less significant than the third. Any such precise population count offered by any source is simply the numeric result of populations statistics, which necessarily used estimates and rough averages as their basis.Even assuming the estimates used as the basis to be significantly accurate the different statistical models are by no means perfect and are constantly being fine tuned. While they may, if done astutely, provide us with a remote idea about the number of humans who have ever lived on the Earth, the margin of error should always be regarded as being in the billions, or even the tens of billions of people.

"Guesstimating the number of people ever born... requires selecting population sizes for different points from antiquity to the present and applying assumed birth rates to each period..."^[20]

According to one set of calculations based on 2002 data:^[20]

• The number who have ever been born is 106,456,367,669 (keeping in mind that with an error rate possibly in the tens of billions, a calculation such as this, given precision to the single digits, is for all intents and purposes arbitrary--beyond the billions level of estimation).
• The world population in mid-2002 was approximately 6,215,000,000
• The percentage of those ever born who were living in 2002 was approximately 5.8%

The claim often made in various popular sources that more than half the humans ever born are alive today, is therefore in all probability quite exaggerated.

See also

• Birth control
• Doomsday argument
• Family planning
• Green Revolution
• Life expectancy
• List of religious populations
• List of countries by population
• List of countries by population density
• List of countries by population growth rate
• List of countries by fertility rate
• List of famines
• Literacy (correlated with population growth)
• Medieval demography
• One child policy
• Overpopulation
• Population control
• The Day of Six Billion
• World largest cities
• World population estimates
• Causes of hypothetical future disasters

References

External links

• Optimum Population Trust
• State of World Population 2007 report 27 June, 2007 - United Nations Population Fund
• World Population Day United Nations: 11 July
• The Day of 6 Billion official homepage
• World Population Prospects. URL accessed on April 7, 2005.
• World Population Counter
• DIE OFF - a population crash resource page
• Trend of growth rate with total global population
• The World in Balance Transcript of two-part PBS' Nova on World Population
• BBC (1999). UN chief welcomes six billionth baby. URL accessed on March 7, 2005.
• Central Intelligence Agency (2004). [https://www.cia.gov/library/publications/the-world-factbook/geos/xx.html CIA The World Factbook 2004]. URL accessed on February 13, 2005.
• United Nations (2001). United Nations Population Information Network. URL accessed on February 13, 2005.
• United States Census Bureau (2004). Historical Estimates of World Population. URL accessed on February 13, 2005.
• PopulationData.net (2005). PopulationData.net - Information and maps about populations around the world.
• Population Reference Bureau www.prb.org - News and issues related to population.
• (French) World Population Clock (2005). WorldPopClock.com - World population clock.
• Population Counter. Real time counter..
• Population Information on population, population growth, population problems, population statistics, and population figures.
• World maps, including maps of population from Year 1 to Year 2300
• Live World Population
• World Population Counter
• World Population Counter
• World Population from the US Census Bureau in an interactive Excel dashboard