Population growth

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Absolute increase in global human population per year Absolute increase in global population per year, OWID.svg
Absolute increase in global human population per year

Population growth is the increase in the number of individuals in a population. Global human population growth amounts to around 83 million annually, [2] or 1.1% per year. The global population has grown from 1 billion in 1800 to 7.8 billion [3] in 2020. It is expected to keep growing, and estimates have put the total population at 8.6 billion by mid-2030, 9.8 billion by mid-2050 and 11.2 billion by 2100. [4] Many nations with rapid population growth have low standards of living, whereas many nations with low rates of population growth have high standards of living. [5]

Contents

Population [6]
Years passedYearBillion
18001
12719272
3319603
1419744
1319875
1219996
1220117
122023*8
142037*9
182055*10
332088*11
*World Population Prospects 2017
(United Nations Population Division)

History

World human population estimates from 1800 to 2100, with estimated range of future population after 2020 based on "high" and "low" scenarios. Data from the United Nations projections in 2019. Human population since 1800.png
World human population estimates from 1800 to 2100, with estimated range of future population after 2020 based on "high" and "low" scenarios. Data from the United Nations projections in 2019.

World population has been rising continuously since the end of the Black Death, around the year 1350. [7] Population began growing rapidly in the Western world during the industrial revolution. The most significant increase in the world's population has been since the 1950s, mainly due to medical advancements [8] and increases in agricultural productivity. [9]

Haber process

Due to its dramatic impact on the human ability to grow food, the Haber process served as the "detonator of the population explosion", enabling the global population to increase from 1.6 billion in 1900 to 7.7 billion by November 2019. [10]

Thomas McKeown hypotheses

Some of the reasons for the "Modern Rise of Population" [11] were particularly investigated by the British health scientist Thomas McKeown (1912-1988). In his publications, McKeown challenged four theories about the population growth:

  1. McKeown stated that the growth in Western population, particularly surging in the 19th century, was not so much caused by an increase in fertility, but largely by a decline of mortality particularly of childhood mortality followed by infant mortality, [12] [13]
  2. The decline of mortality could largely be attributed to rising standards of living, whereby McKeown put most emphasis on improved nutritional status,
  3. His most controversial idea, at least his most disputed idea, was that he questioned the effectiveness of public health measures, including sanitary reforms, vaccination and quarantine, [14]
  4. The sometime fierce disputes that his publication provoked around the "McKeown thesis", have overshadowed his more important and largely unchallenged argument that curative medicine measures played little role in mortality decline, not only prior to the mid-20th century [12] but also until well into the 20th century. [15]

Although the McKeown thesis has been heavily disputed, recent studies have confirmed the value of his ideas. [16] His work is pivotal for present day thinking about population growth, birth control, public health and medical care. McKeown had a major influence on many population researchers, such as health economists and Nobel prize winners Robert W. Fogel (1993) and Angus Deaton (2015). The latter considered McKeown as "the founder of social medicine". [17]

Population growth rate

External video
Nuvola apps kaboodle.svg Human Population Through Time

The "population growth rate" is the rate at which the number of individuals in a population increases in a given time period, expressed as a fraction of the initial population. Specifically, population growth rate refers to the change in population over a unit time period, often expressed as a percentage of the number of individuals in the population at the beginning of that period. This can be written as the formula, valid for a sufficiently small time interval:

A positive growth rate indicates that the population is increasing, while a negative growth rate indicates that the population is decreasing. A growth ratio of zero indicates that there were the same number of individuals at the beginning and end of the period—a growth rate may be zero even when there are significant changes in the birth rates, death rates, immigration rates, and age distribution between the two times. [18]

A related measure is the net reproduction rate. In the absence of migration, a net reproduction rate of more than 1 indicates that the population of females is increasing, while a net reproduction rate less than one (sub-replacement fertility) indicates that the population of females is decreasing.

Most populations do not grow exponentially, rather they follow a logistic model. Once the population has reached its carrying capacity, it will stabilize and the exponential curve will level off towards the carrying capacity, which is usually when a population has depleted most its natural resources. [19]

The logistic growth of a population. Logistic growth graph (population ecology).JPG
The logistic growth of a population.

Logistic equation

The growth of a population can often be modelled by the logistic equation [20]

where

As it is a separable differential equation, the population may be solved explicitly, producing a logistic function:

,

where and is the initial population at time 0.

Human population growth rate

External video
Nuvola apps kaboodle.svg How Earth's Population Exploded
A world map showing global variations in fertility rate per woman according to the CIA World Factbook's 2016 data
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7-8 children
6-7 children
5-6 children
4-5 children
3-4 children
2-3 children
1-2 children
0-1 children Countriesbyfertilityrate.svg
A world map showing global variations in fertility rate per woman according to the CIA World Factbook's 2016 data
Estimates of population evolution in different continents between 1950 and 2050 according to the United Nations. The vertical axis is logarithmic and is in millions of people. World population (UN).svg
Estimates of population evolution in different continents between 1950 and 2050 according to the United Nations. The vertical axis is logarithmic and is in millions of people.
World population growth rates between 1950-2050 World population growth rate 1950-2050.svg
World population growth rates between 1950–2050

In 2017, the estimated annual growth rate was 1.1%. [21] The CIA World Factbook gives the world annual birthrate, mortality rate, and growth rate as 1.86%, 0.78%, and 1.08% respectively. [22] The last 100 years have seen a massive fourfold increase in the population, due to medical advances, lower mortality rates, and an increase in agricultural productivity [23] made possible by the Green Revolution.

The annual increase in the number of living humans peaked at 88.0 million in 1989, then slowly declined to 73.9 million in 2003, after which it rose again to 75.2 million in 2006. In 2017, the human population increased by 83 million. [21] Generally, developed nations have seen a decline in their growth rates in recent decades, though annual growth rates remain above 2% in poverty-stricken countries of the Middle East and Sub-Saharan Africa, and also in South Asia, Southeast Asia, and Latin America. [24]

In some countries the population is declining, especially in Eastern Europe, mainly due to low fertility rates, high death rates and emigration. In Southern Africa, growth is slowing due to the high number of AIDS-related deaths. Some Western Europe countries might also experience population decline. [25] Japan's population began decreasing in 2005. [26]

The United Nations Population Division projects world population to reach 11.2 billion by the end of the 21st century, but Sanjeev Sanyal has argued that global fertility will fall below the replacement rate in the 2020s and that world population will peak below 9 billion by 2050, followed by a long decline. [27] A 2014 study in Science concludes that the global population will reach 11 billion by 2100, with a 70% chance of continued growth into the 22nd century. [28]

For further information regarding Human Population Growth, one could see the works of Al Bartlett, Hans Rosling, John Lovelock, Paul R. Ehrlich as well as Cleric Thomas Robert Malthus.

Growth by country

According to United Nations population statistics, the world population grew by 30%, or 1.6 billion humans, between 1990 and 2010. [29] In number of people the increase was highest in India (350 million) and China (196 million). Population growth rate was among highest in the United Arab Emirates (315%) and Qatar (271%). [29]

Growth rates of the world's most populous countries
RankCountryPopulation
1990
Population
2010
Estimated population

2018 [30]

Growth (%)
1990–2010
Growth (%) 2010–2018
World 5,306,425,0006,895,889,0007,503,828,18030.0%
1 Flag of the People's Republic of China.svg China 1,139,060,0001,341,335,0001,384,688,98617.1%3.23%
2 Flag of India.svg India 873,785,0001,224,614,0001,296,834,04240.2%5.90%
3 Flag of the United States.svg United States 253,339,000310,384,000329,256,46522.5%6.08%
4 Flag of Indonesia.svg Indonesia 184,346,000239,871,000262,787,40330.1%9.55%
5 Flag of Brazil.svg Brazil 149,650,000194,946,000208,846,89230.3%7.13%
6 Flag of Pakistan.svg Pakistan 111,845,000173,593,000207,862,51855.3%19.74%
7 Flag of Nigeria.svg Nigeria 97,552,000158,423,000203,452,50562.4%28.42%
8 Flag of Bangladesh.svg Bangladesh 105,256,000148,692,000159,453,00141.3%7.24%
9 Flag of Russia.svg Russia 148,244,000142,958,000142,122,776-3.6%-0.58%
10 Flag of Japan.svg Japan 122,251,000128,057,000126,168,1564.7%-1.48%

Many of the world's countries, including many in Sub-Saharan Africa, the Middle East, South Asia and South East Asia, have seen a sharp rise in population since the end of the Cold War. The fear is that high population numbers are putting further strain on natural resources, food supplies, fuel supplies, employment, housing, etc. in some of the less fortunate countries. For example, the population of Chad has ultimately grown from 6,279,921 in 1993 to 10,329,208 in 2009, [31] further straining its resources. Vietnam, Mexico, Nigeria, Egypt, Ethiopia, and the DRC are witnessing a similar growth in population.

The following table gives some example countries:

Example nation1967 population1990 population1994 population2002 population2008 populationLife expectancy in years (2008)Total population growth from 1960s to 2007- 2011
Flag of Eritrea.svg Eritrea*N/A*N/A*3,437,000 [32] 4,298,2695,673,520 [33] 61 [34] 2,236,520
Flag of Ethiopia.svg Ethiopia*23,457,000* [35] 50,974,000* [36] 54,939,000 [32] 67,673,031(2003)79,221,000 [37] 55 [34] 55,764,000
Flag of Sudan.svg Sudan 14,355,000† [35] 25,204,000† [36] 27,361,000† [32] 38,114,160 (2003)†42,272,000† [33] 50† [34] 27,917,000
Flag of Chad.svg Chad 3,410,000 [35] 5,679,000 [36] 6,183,000 [32] 9,253,493(2003)10,329,208 (2009) [31] 47 [34] 6,919,205
Flag of Niger.svg Niger 3,546,000 [35] 7,732,000 [36] 8,846,000 [32] 10,790,352 (2001)15,306,252 (2009) [38] 44 [34] 11,760,252
Flag of Nigeria.svg Nigeria 61,450,000 [35] 88,500,000 [36] 108,467,000 [32] 129,934,911158,259,000 [33] 47 [34] 96,809,000
Flag of Mali.svg Mali 4,745,000 [35] 8,156,000 [36] 10,462,000 [32] 11,340,48014,517,176(2010) [39] 50 [34] 9,772,176
Flag of Mauritania.svg Mauritania 1,050,000 [35] 2,025,000 [36] 2,211,000 [32] 2,667,859 (2003)3,291,000 (2009) [31] 54 [34] 2,241,000
Flag of Senegal.svg Senegal 3,607,000 [35] 7,327,000 [36] 8,102,000 [32] 9,967,21513,711,597 (2009) [40] 57 [34] 10,104,597
Flag of The Gambia.svg Gambia 343,000 [35] 861,000 [36] 1,081,000 [32] 1,367,124 (2000)1,705,000 [33] 55 [34] 1,362,000
Flag of Algeria.svg Algeria 11,833,126 (1966) [35] 25,012,000 [36] 27,325,000 [32] 32,818,500 (2003)34,895,000 [37] [41] 74 [34] 23,061,874
Flag of the Democratic Republic of the Congo.svg The DRC/Zaire 16,353,000 [35] 35,562,000 [36] 42,552,000 [32] 55,225,478 (2003)70,916,439 [37] [42] 54 [34] 54,563,439
Flag of Egypt.svg Egypt 30,083,419 (1966) [35] 53,153,000 [36] 58,326,000 [32] 70,712,345 (2003)79,089,650 [37] [43] 72 [34] 49,006,231
Flag of France.svg Réunion (overseas region of France)418,000 [35] N/A [36] N/A [32] 720,934 (2003)827,000 (2009) [33] N/A [34] 409,000
Flag of the Falkland Islands.svg The Falkland Islands (British Overseas Territory)2,500 [35] N/A [36] N/A [32] 2,967 (2003)3,140(2010) [44] N/A [34] 640
Flag of Chile.svg Chile 8,935,500 [35] 13,173,000 [36] 13,994,000 [32] 15,116,43517,224,200 (2011)77 [34] 8,288,700
Flag of Colombia.svg Colombia 19,191,000 [35] 32,987,000 [36] 34,520,000 [32] 41,088,22745,925,397 (2010) [45] 73 [34] 26,734,397
Flag of Brazil.svg Brazil 85,655,000 [35] 150,368,000 [36] 153,725,000 [32] 174,468,575 (2000)190,732,694 (2010) [46] 72 [34] 105,077,694
Flag of Brazil.svg Mexico 45,671,000 [35] 86,154,000 [36] 93,008,000 [32] 103,400,165 (2000)112,322,757 (2010) [47] 76 [34] 66,651,757
Flag of Fiji.svg Fiji 476,727 (1966) [35] 765,000 [36] 771,000 [32] 844,330 (2001)849,000 [41] (2010)70 [34] 372,273
Flag of Nauru.svg Nauru 6,050 (1966) [35] 10,000 [36] N/A [32] 12,3299,322 (2011) [48] N/A [34] 3,272
Flag of Jamaica.svg Jamaica 1,876,000 [35] 2,420,000 [36] 2,429,000 [32] 2,695,867 (2003)2,847,232 [49] (2010)74 [34] 971,232
Flag of Australia (converted).svg Australia 11,540,764 (1964) [35] 17,086,000 [36] 17,843,000 [32] 19,546,792 (2003)25,701,639 [50] (2010)82 [34] 10,066,508
Flag of Albania.svg Albania 1,965,500 (1964) [35] 3,250,000 [36] 3,414,000 [32] 3,510,4842,986,952 (July 2010 est.) [31] [51] 78 [34] 1,021,452
Flag of Poland.svg Poland 31,944,000 [35] 38,180,000 [36] 38,554,000 [32] 38,626,349 (2001)38,192,000 (2010) [52] 75 [34] 6,248,000
Flag of Hungary.svg Hungary 10,212,000 [35] 10,553,000 [36] 10,261,000 [32] 10,106,0179,979,000 (2010) [53] 73 [34] -142,000
Flag of Bulgaria.svg Bulgaria 8,226,564 (1965) [35] 8,980,000 [36] 8,443,000 [32] 7,707,495(2000)7,351,234 (2011) [54] 73 [34] -875,330
Flag of the United Kingdom.svg United Kingdom 55,068,000 (1966) [35] 57,411,000 [36] 58,091,000 [32] 58,789,19462,008,048 (2010) [55] 79 [34] 7,020,048
Flag of Ireland.svg Ireland 2,884,002 (1966) [35] 3,503,000 [36] 3,571,000 [32] 3,840,838 (2000)4,470,700 [56] (2010)78 [34] 1,586,698
Flag of the People's Republic of China.svg People's Republic of China 720,000,000 [35] 1,139,060,000 [36] 1,208,841,000 [32] 1,286,975,468 (2004)1,339,724,852 (2010) [57] 73 [34] 619,724,852
Flag of Japan.svg Japan98,274,961 (1965) [35] 123,537,000 [36] 124,961,000 [32] 127,333,002127,420,000 (2010) [58] 82 [34] 28,123,865
Flag of India.svg India#511,115,000 [35] 843,931,000 [36] 918,570,000 [32] 1,028,610,328 (2001)1,210,193,422 (2011) [59] 69 [34] 699,078,422
Flag of Singapore.svg Singapore 1,956,000 (1967) [35] 3,003,000 (1990) [36] 2,930,000 (1994) [32] 4,452,732 (2002)5,076,700 (2010) [60] 82 (2008) [34] 3,120,700
Flag of Monaco.svg Monaco 24,000 (1967) [35] 29,000 (1990) [36] N/A (1994) [32] 31,842 (2000)35,586 [61] (2010)(2008) [34] 11,586
Flag of Greece.svg Greece 8,716,000 (1967) [35] 10,123,000 (1990) [36] 10,426,000 (1994) [32] 10,964,020 (2001) [62] 11,305,118 (2011) [63] N/A (2008) [34] 2,589,118
Flag of the Faroe Islands.svg Faroe Islands (Danish dependency)38,000 (1967) [35] N/A (1990) [36] N/A (1994) [32] 46,345 (2000)48,917 (2010) [64] N/A (2008) [34] 18,917
Flag of Liechtenstein.svg Liechtenstein 20,000 (1967) [35] 29,000 (1990) [36] N/A (1994) [32] 33,307 (2000)35,789 (2009) [65] (2008) [34] 15,789
Flag of South Korea.svg South Korea 29,207,856 (1966) [35] 42,793,000 (1990) [36] 44,453,000 (1994) [32] 48,324,000 (2003)48,875,000 (2010) [66] (2008) [34] 19,667,144
Flag of North Korea.svg North Korea 12,700,000 (1967) [35] 21,773,000 (1990) [36] 23,483,000 (1994) [32] 22,224,195 (2002)24,051,218 (2010) [67] (2008) [34] 11,351,218
Flag of Brunei.svg Brunei 107,200 (1967) [35] 266,000 (1990) [36] 280,000 (1994) [32] 332,844 (2001)401,890 (2011) [68] 76 (2008) [34] 306,609
Flag of Malaysia.svg Malaysia 10,671,000 (1967) [35] 17,861,000 (1990) [36] 19,489,000 (1994) [32] 21,793,293 (2002)27,565,821 (2010) [69] (2008) [34] 16,894,821
Flag of Thailand.svg Thailand 32,680,000 (1967) [35] 57,196,000 (1990) [36] 59,396,000 (1994) [32] 60,606,947 (2000) [70] 63,878,267 (2011) [71] (2008) [34] 31,198,267
Flag of Lebanon.svg Lebanon 2,520,000 (1967) [35] 2,701,000 (1990) [36] 2,915,000 (1994) [32] 3,727,703 [72] (2003)4,224,000 [33] (2009)- (2008) [34]
Flag of Syria.svg Syria 5,600,000 (1967) [35] 12,116,000 (1990) [36] 13,844,000 (1994) [32] 17,585,540 (2003)22,457,763 (2011) [73] -(2008) [34]
Flag of Bahrain.svg Bahrain 182,00 (1967) [35] 503,000 (1990) [36] 549,000 (1994) [32] 667,238 (2003)1,234,596 [74] (2010)75 (2008) [34]
Flag of Sri Lanka.svg Sri Lanka 11,741,000 (1967) [35] 16,993,000 (1990) [36] 17,685,000 (1994) [32] 19,607,519 (2002)20,238,000 [41] (2009)- (2008) [34]
Flag of Switzerland.svg Switzerland 6,050,000 (1967) [35] 6.712,000 (1990) [36] 6,994,000 (1994) [32] 7,261,200 (2002)7,866,500 [75] (2010)- (2008) [34]
Flag of Luxembourg.svg Luxembourg 335,000 (1967) [35] 381,000 (1990) [36] 401,000 (1994) [32] 439,539 (2001)511,840 (2011) [76] - (2008) [34]
Flag of Romania.svg Romania 19,105,056 (1966) [35] 23,200,000 (1990) [36] 22,736,000 (1994) [32] 21,680,974 (2002)21,466,174 [77] (2011)- (2008) [34]
Flag of Niue.svg Niue (associated state of New Zealand)1,900 (1966) [35] N/A (1990) [36] N/A (1994) [32] 2,134 (2002)1,398 (2009) [78] N/A (2008) [34] -502
Flag of Tokelau.svg Tokelau (New Zealand territory)5,194 (1966) [35] N/A (1990) [36] N/A (1994) [32] 1,445 (2001)1,416 (2009)N/A (2008) [34] -3,778
Flag of Jamaica.svg Jamaica 1,876,000 (1967) [35] 2,420,000 (1990) [36] 2,429,000 (1994) [32] 2,695,867 (2003)2,847,232 [49] (2010)74 (2008) [34] 971,232
Flag of Argentina.svg Argentina 32,031,000 (1967) [35] 32,322,000 (1990) [36] 34,180,000 (1994) [32] 37,812,817 (2002)40,091,359 (2010)74 (2008) [34] 8,060,359
Flag of France.svg France 49,890,660 (1967) [35] 56,440,000 (1990) [36] 57,747,000 (1994) [32] 59,551,000 (2001)63,136,180 (2011) [79] 81 (2008) [34]
Flag of Italy.svg Italy 52,334,000 (1967) [35] 57,662,000 (1990) [36] 57,193,000 (1994) [32] 56,995,744 (2002)60,605,053 [80] (2011)80 (2008) [34]
Flag of Mauritius.svg Mauritius 774,000 (1967) [35] 1,075,000 (1990) [36] 1,104,000 (1994) [32] 1,179,137 (2000)1,288,000 (2009) [41] 75 (2008) [34] 514,000
Flag of Guatemala.svg Guatemala 4,717,000 (1967) [35] 9,197,000 (1990) [36] 10,322,000 (1994) [32] 12,974,361 (2000)13,276,517 (2009)70 (2008) [34] 8,559,517
Flag of Cuba.svg Cuba 8,033,000 (1967) [35] 10,609,000 (1990) [36] 10,960,000 (1994) [32] 11,177,743 (2002)11,239,363 (2009) [81] 77 (2008) [34]
Flag of Barbados.svg Barbados 246,000 (1967) [35] 255,000 (1990) [36] 261,000 (1994) [32] 250,012 (2001)284,589 (2010) [31] 73 (2008) [34] 18,589
Flag of Samoa.svg Samoa 131,377 (1967) [35] 164,000 (1990) [36] 164,000 (1994) [32] 178,173 (2003)179,000 (2009) [33] N/A (2008) [34]
Flag of Sweden.svg Sweden 7,765,981 (1967) [35] 8,559,000 (1990) [36] 8,794,000 (1994) [32] 8,920,705 (2002)9,354,462 (2009)81 (2008) [34]
Flag of Finland.svg Finland 4,664,000 (1967) [35] 4,986,000 (1990) [36] 5,095,000 (1994) [32] 5,175,783 (2002)5,374,781 (2010)N/A (2008) [34]
Flag of Portugal.svg Portugal 9,440,000 (1967) [35] 10,525,000 (1990) [36] 9,830,000 (1994) [32] 10,355,824 (2001)10,647,763 [82] (2011)N/A (2008) [34]
Flag of Austria.svg Austria 7,323,981 (1967) [35] 7,712,000 (1990) [36] 8,031,000 (1994) [32] 8,032,926 (2001)8,404,252 (2011)N/A (2008) [34]
Flag of Libya.svg Libya 1,738,000 (1967) [35] 4,545,000 (1990) [36] 5,225,000(1994) [32] 5,499,074 (2002)6,420,000 (2009) [33] 77 (2008) [34]
Flag of Peru.svg Peru 12,385,000 (1967) [35] 21,550,000 (1990) [36] 23,080,000(1994) [32] 27,949,639 (2002)29,496,000 (2010)70 (2008) [34]
Flag of Guinea-Bissau.svg Guinea Bissau 528,000 (1967) [35] 965,000 (1990) [36] 1,050,000 (1994) [32] 1,345,479 (2002)1,647,000 [33] (2009)48 (2008) [34]
Flag of Angola.svg Angola 5,203,066 (1967) [35] 10,020,000 (1990) [36] 10,674,000 (1994) [32] 10,766,500 (2003)18,498,000 [41] [83] (2009)38 (2008) [34]
Flag of Equatorial Guinea.svg Equatorial Guinea 277,000 (1967) [35] 348,000 (1990) [36] 389,000 (1994) [32] 474,214 (2000)676,000 (2009) [41] 61 (2008) [34]
Flag of Benin.svg Benin 2,505,000 (1967) [35] 4,736,000 (1990) [36] 5,246,000 (1994) [32] 8,500,500 (2002)8,791,832 (2009)59 (2008) [34]
Flag of Laos.svg Laos 2,770,000 (1967) [35] 4,139,000 (1990) [36] 4,742,000 (1994) [32] 5,635,967 (2002)6,800,000 [84] (2011)56 (2008) [34]
Flag of Nepal.svg Nepal 10,500,000 (1967) [35] 18,961,000 (1990) [36] 21,360,000 (1994) [32] 25,284,463 (2002)29,331,000 [41] (2009)- (2008) [34]
Flag of Iran.svg Iran 25,781,090 (1966) [35] 54,608,000 (1990) [36] 59,778,000 (1994) [32] 66,622,704 (2002)75,330,000 (2010) [85] 71 (2008) [34] 49,548,910
Flag of Canada (Pantone).svg Canada 20,014,880 (1966) [35] 26,603,000 (1990) [36] 29,248,000(1994) [32] 31,081,900 (2001)32,623,490 (2011) [86] 81 (2008) [34]
Flag of the United States.svg United States 199,118,000 (1967) [35] 249,995,000 (1990) [36] 260,650,00(1994) [32] 281,421,906 (2000)308,745,538 (2010) [87] 78 (2008) [34]
Flag of Uganda.svg Uganda 7,931,000 (1967) [35] 18,795,000 (1990) [36] 20,621,000 (1994) [32] 24,227,297 (2002)32,369,558 (2009)52 (2008) [34]
Notes
* Eritrea left Ethiopia in 1991.
Split into the nations of Sudan and South Sudan during 2011.
Japan and the Ryukyu Islands merged in 1972.
# India and Sikkim merged in 1975.
Population growth 1990–2012 (%) [88]
Africa 73.3%
Middle East 68.2%
Asia (excl. China)42.8%
China 19.0%
OECD Americas 27.9%
Non-OECD Americas36.6%
OECD Europe 11.5%
OECD Asia Oceania 11.1%
Non-OECD Europe and Eurasia -0.8%
Nilkhet Mor in Dhaka by Nahid 02. Bangladesh is one fo the most densely populated countries in the world. Nilkhet Mor in Dhaka by Nahid 02.jpg
Nilkhet Mor in Dhaka by Nahid 02. Bangladesh is one fo the most densely populated countries in the world.

Growth comparison between Africa and Europe

Population growth rates vary by world region, with the highest growth rates in Sub-Saharan Africa and the lowest in Europe. For example, from 1950 to 2010, Sub-Saharan Africa grew over four and a half times, from about 186 million to 856 million. On the other hand, Europe only increased by 35%, from 547 million in 1950 to 738 million in 2010. As a result of these varying population growths, Sub-Saharan Africa changed from 7.4% of world population in 1950 to 12.4% in 2010, while Europe declined from 22% to 11% in the same time period. [89]

Into the future

Estimated size of human population from 10,000 BCE to 2000 CE. Population curve.svg
Estimated size of human population from 10,000 BCE to 2000 CE.
The majority of world population growth today is occurring in less developed countries. Comparing Population Growth By Country's Development, 2002.svg
The majority of world population growth today is occurring in less developed countries.

According to the UN's 2017 revision to its population projections, world population is projected to reach 11.2 billion by 2100 compared to 7.6 billion in 2017. [90] [91] In 2011, Indian economist Sanjeev Sanyal disputed the UN's figures and argued that birth rates will fall below replacement rates in the 2020s. According to his projections, population growth will be only sustained till the 2040s by rising longevity, but will peak below 9 bn by 2050. [27] Conversely, a 2014 paper by demographers from several universities and the United Nations Population Division projected that the world's population would reach about 10.9 billion in 2100 and continue growing thereafter. [92] One of its authors, Adrian Raftery, a University of Washington professor of statistics and of sociology, says "The consensus over the past 20 years or so was that world population, which is currently around 7 billion, would go up to 9 billion and level off or probably decline. We found there’s a 70 percent probability the world population will not stabilize this century. Population, which had sort of fallen off the world’s agenda, remains a very important issue." [93]

The German Foundation for World Population reported in December 2019 that the global human population grows by 2.6 people every second, and could reach 8 billion by 2023. [94]

See also

Related Research Articles

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Mortality rate Measure of the number of deaths in a population from a given cause, scaled by population, in a set period of time

Mortality rate, or death rate, is a measure of the number of deaths in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of deaths per 1,000 individuals per year; thus, a mortality rate of 9.5 in a population of 1,000 would mean 9.5 deaths per year in that entire population, or 0.95% out of the total. It is distinct from "morbidity", which is either the prevalence or incidence of a disease, and also from the incidence rate.

A population decline in humans is a reduction in a human population size caused by short term events such as pandemics, wars, famines or other catastrophes, or by long-term demographic trends, as in sub-replacement fertility rate, or persistent emigration.

Human overpopulation Condition where human numbers exceed the short or long-term carrying capacity of the environment

Human overpopulation is a state in which there are too many people for the environment to sustain. In more scientific terms, there is overshoot when the ecological footprint of a human population in a geographical area exceeds that place's carrying capacity, damaging the environment faster than it can be repaired by nature, potentially leading to an ecological and societal collapse. Overpopulation could apply to the population of a specific region, or to world population as a whole.

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World population Total number of living humans on Earth

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The Earth has a population of 7.8 billion, with an overall population density of 50 people per km2, excluding Antarctica. Nearly two-thirds of the world's population lives in Asia, with more than 2.7 billion in the countries of China and India combined. The world's literacy rate has increased dramatically in the last 40 years, from 66.7% in 1979 to 86.3% today. Lower literacy levels are mostly attributable to poverty. Lower literacy rates are mostly found in South Asia, West Asia and Sub-Saharan Africa. The world's largest ethnic group is Han Chinese, with Mandarin being the world's most spoken language in terms of native speakers.

Projections of population growth World population growth projections

Population projections are attempts to show how the human population living today will change in the future. These projections are an important input to forecasts of the population's impact on this planet and humanity's future well-being.

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