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Population growth
http://en.wikipedia.org/wiki/Population_growth
From Wikipedia, the free encyclopedia
The estimated size of the human population from 10,000 BCE–2000 CE.
In biology, population growth is the increase in the number of individuals in a population. The population growth rate is the rate at which the number of individuals in a population increases in a given time period as a fraction of the initial population.
Global human population growth amounts to around 75 million annually, or 1.1% per year. The global population has grown from 1 billion in 1800 to 7 billion in 2012. It is expected to keep growing, where estimates have put the total population at 8.4 billion by mid-2030, and 9.6 billion by mid-2050.[1]
| Population[2] | ||
| Years Passed | Year | Billion |
| – | 1800 | 1 |
| 127 | 1927 | 2 |
| 33 | 1960 | 3 |
| 14 | 1974 | 4 |
| 13 | 1987 | 5 |
| 12 | 1999 | 6 |
| 12 | 2011 | 7 |
| 14 | 2025* | 8 |
| 18 | 2043* | 9 |
| 40 | 2083* | 10 |
| * UNFPA United Nations Population Fund estimate 31.10.2011 | ||
Contents
- 1 Population growth rate
- 2 Human population growth rate
- 3 Growth by country
- 3.1 1960s to 2010 table of population growth
- 4 Into the future
- Population growth rate
The “population growth rate” is the rate at which the number of individuals in a population increases in a given time period 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:
A positive growth ratio (or rate) indicates that the population is increasing, while a negative growth ratio indicates the population is decreasing. A growth ratio of zero indicates that there were the same number of people at the two times—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.[3]
A related measure is the net reproduction rate. In the absence of migration, a net reproduction rate of more than one indicates that the population of women is increasing, while a net reproduction rate less than one (sub-replacement fertility) indicates that the population of women is decreasing.
- Human population growth rate
Main article: Total fertility rate
A world map showing global variations in fertility rate per woman, according to the CIA World Factbook‘s 2013 data.
| Dark Purple – 7–8 childrenPink – 6–7 children | Red – 5–6 childrenOrange – 4–5 children | Yellow – 3–4 childrenGreen – 2–3 children | Light Blue -1–2 childrenBlue – 0–1 children |
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.
Growth rate of world population (1950–2050).
Globally, the growth rate of the human population has been declining since peaking in 1962 and 1963 at 2.20% per annum. In 2009, the estimated annual growth rate was 1.1%.[4] The CIA World Factbook gives the world annual birthrate, mortality rate, and growth rate as 1.89%, 0.79%, and 1.096% respectively.[5] The last 100 years have seen a rapid increase in population due to medical advances and massive increase in agricultural productivity[6] made possible by the Green Revolution.[7][8][9]
The actual annual growth in the number of humans fell from its peak of 88.0 million in 1989, to a low of 73.9 million in 2003, after which it rose again to 75.2 million in 2006. Since then, annual growth has declined. In 2009, the human population increased by 74.6 million, which is projected to fall steadily to about 41 million per annum in 2050, at which time the population will have increased to about 9.2 billion.[4] Each region of the globe has seen great reductions in growth rate in recent decades, though growth rates remain above 2% in some countries of the Middle East and Sub-Saharan Africa, and also in South Asia, Southeast Asia, and Latin America.[10]
Some countries experience negative population growth, 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 HIV-related deaths. Some Western Europe countries might also encounter negative population growth.[11] Japan‘s population began decreasing in 2005.[12] The United Nations Population Division expects world population to peak at over 10 billion at the end of the 21st century but Sanjeev Sanyal has argued that global fertility will fall below replacement rates in the 2020s and that world population will peak below 9 billion by 2050 followed by a long decline.[13]
- Growth by country
According to United Nations population statistics, the world population grew by 30%, or 1.6 billion people, between 1990 and 2010.[14] In number of people the increase was highest in India (350 million) and China (196 million). Population growth was among highest in the United Arab Emirates (315%) and Qatar (271%).[14]
| Growth rates of the world’s most populous countries | ||||
| Rank | Country | Population 2010 | Population 1990 | Growth (%) 1990–2010 |
| World | 6,895,889,000 | 5,306,425,000 | 30.0% | |
| 1 | China | 1,341,335,000 | 1,145,195,000 | 17.1% |
| 2 | India | 1,224,614,000 | 873,785,000 | 40.2% |
| 3 | United States | 310,384,000 | 253,339,000 | 22.5% |
| 4 | Indonesia | 239,871,000 | 184,346,000 | 30.1% |
| 5 | Brazil | 194,946,000 | 149,650,000 | 30.3% |
| 6 | Pakistan | 173,593,000 | 111,845,000 | 55.3% |
| 7 | Nigeria | 158,423,000 | 97,552,000 | 62.4% |
| 8 | Bangladesh | 148,692,000 | 105,256,000 | 41.3% |
| 9 | Russia | 142,958,000 | 148,244,000 | -3.6% |
| 10 | Japan | 128,057,000 | 122,251,000 | 4.7% |
3.1 1960s to 2010 table of population growth
| Population growth 1990–2008 (%)[15] | |
| Africa | 55% |
| Middle East | 51% |
| Asia | 35% |
| Latin America | 30% |
| OECD North America | 24% |
| OECD Europe | 9% |
| OECD Pacific | 8% |
| Former Soviet Union | −1% |
| Non-OECD Europe | -00000] |
| Example nation | 1st Population total. | 2nd Population total. | 3rd Population total. | 4th Population total. | 5th Population total. | Life expectancy in years. | Total population growth from 1st Pop. Total to 5th Pop. Total. |
| Eritrea* | N/A* | N/A* | 3,437,000(1994)[16] | 4,298,269 (2002) | 5,673,520 (2008)[17] | 61 (2008)[18] | 2,236,520 (since independence) |
| Ethiopia* | 23,457,000(1967)*[19] | 50,974,000(1990)* [20] | 54,939,000(1994) [16] | 67,673,031(2003) | 79,221,000(2008)[21] | 55(2008)[18] | 55,764,000 |
| Sudan** | 14,355,000(1967)**[19] | 25,204,000(1990)** [20] | 27,361,000 (1994)**[16] | 38,114,160 (2003)** | 42,272,000(2008)**[22] | 50(2008)**[18] | 27,917,000 |
| Chad | 3,410,000(1967)[19] | 5,679,000(1990) [20] | 6,183,000 (1994)[16] | 9,253,493(2003) | 10,329,208 (2009)[23] | 47(2008)[18] | 6,919,205 |
| Niger | 3,546,000(1967)[19] | 7,732,000(1990) [20] | 8,846,000(1994)[16] | 10,790,352 (2001) | 15,306,252 (2009)[24] | 44 (2008)[18] | 11,760,252 |
| Nigeria | 61,450,000(1967)[19] | 88,500,000(1990) [20] | 108,467,000 (1994)[16] | 129,934,911 (2002) | 158,259,000 (2008)[25] | 47(2008)[18] | 96,809,000 |
| Mali | 4,745,000(1967)[19] | 8,156,000(1990),[20] | 10,462,000(1994)[16] | 11,340,480(2002) | 14,517,176(2010).[26] | 50(2008)[18] | 9,772,176 |
| Mauritania | 1,050,000(1967)[19] | 2,025,000(1990) [20] | 2,211,000 (1994)[16] | 2,667,859 (2003) | 3,291,000 (2009)[23] | 54(2008)[18] | 2,241,000 |
| Senegal | 3,607,000(1967)[19] | 7,327,000(1990) [20] | 8,102,000 (1994) [16] | 9,967,215(2002) | 13,711,597 (2009)[27] | 57(2008)[18] | 10,104,597 |
| Gambia | 343,000(1967)[19] | 861,000(1990) [20] | 1,081,000 (1994)[16] | 1,367,124 (2000) | 1,705,000(2008)[25] | 55(2008)[18] | 1,362,000 |
| Algeria | 11,833,126 (1966)[19] | 25,012,000 (1990) [20] | 27,325,000 (1994) [16] | 32,818,500 (2003) | 34,895,000[21][28](2008) | 74 (2008)[18] | 23,061,874 |
| The DRC/Zaire | 16,353,000(1967)[19] | 35,562,000 (1990) [20] | 42,552,000 (1994) [16] | 55,225,478 (2003) | 70,916,439 (2008) [21][29] | 54(2008)[18] | 54,563,439 |
| Egypt | 30,083,419 (1966)[19] | 53,153,000 (1990) [20] | 58,326,000 (1994) [16] | 70,712,345 (2003) | 79,089,650 [30][30] (2008) [21] | 72 (2008)[18] | 49,006,231 |
| Réunion (French colony) | 418,000 (1967)[19] | N/A (1990) [20] | N/A (1994)[16] | 720,934 (2003) | 827,000 (2009) [28] | N/A (2008)[18] | 409,000 |
| The Falkland Islands (UK Territory) | 2,500(1967)[19] | N/A (1990) [20] | N/A (1994)[16] | 2,967 (2003) | 3,140(2010)[23] | N/A (2008)[18] | 640 |
| Chile | 8,935,500(1967)[19] | 13,173,000 (1990) [20] | 13,994,000(1994)[16] | 15,116,435 (2002) | 17,224,200 (2011) | 77 (2008)[18] | 8,288,700 |
| Colombia | 19,191,000(1967)[19] | 32,987,000(1990) [20] | 34,520,000(1994)[16] | 41,088,227 (2002) | 45,925,397(2010)[31] | 73 (2008)[18] | 26,734,397 |
| Brazil | 85,655,000(1967)[19] | 150,368,000 (1990) [20] | 153,725,000 (1994)[16] | 174,468,575 (2000) | 190,732,694(2010) [32] | 72(2008)[18] | 105,077,694 |
| Mexico | 45,671,000(1967)[19] | 86,154,000(1990) [20] | 93,008,000(1994)[16] | 103,400,165 (2000) | 112,322,757(2010)[33] | 76(2008)[18] | 66,651,757 |
| Fiji | 476,727 (1966)[19] | 765,000(1990) [20] | 771,000 (1994)[16] | 844,330 (2001) | 849,000[28] (2010) | 70 (2008)[18] | 372,273 |
| Nauru | 6,050(1966)[19] | 10,000(1990) [20] | N/A (1994)[16] | 12,329 (2002) | 9,322 (2011)[34] | N/A (2008)[18] | 3,272 |
| Jamaica | 1,876,000 (1967)[19] | 2,420,000 (1990) [20] | 2,429,000 (1994)[16] | 2,695,867 (2003) | 2,847,232[35](2010) | 74 (2008)[18] | 971,232 |
| Australia | 11,540,764 (1964)[19] | 17,086,000 (1990) [20] | 17,843,000 (1994)[16] | 19,546,792 (2003) | 23,818,654[36] (2010) | 82 (2008)[18] | 11,066,508 |
| Albania | 1,965,500(1964)[19] | 3,250,000 (1990) [20] | 3,414,000 (1994)[16] | 3,510,484 (2002) | 2,986,952 (July 2010 est.)[23][37] (2010) | 78 (2008)[18] | 1,021,452 |
| Poland | 31,944,000(1967)[19] | 38,180,000 (1990) [20] | 38,554,000 (1994)[16] | 38,626,349 (2001) | 38,192,000(2010)[38] | 75 (2008)[18] | 6,248,000 |
| Hungary | 10,212,000(1967)[19] | 10,553,000 (1990) [20] | 10,261,000 (1994)[16] | 10,106,017 (2002) | 9,979,000(2010)[39] | 73 (2008)[18] | -142,000 |
| Bulgaria | 8,226,564(1965)[19] | 8,980,000 (1990) [20] | 8,443,000 (1994)[16] | 7,707,495(2000) | 7,351,234 (2011)[40] | 73 (2008)[18] | -875,330 |
| UK | 55,068,000 (1966)[19] | 57,411,000 (1990) [20] | 58,091,000 (1994) [16] | 58,789,194 (2002) | 62,008,048 (2010)[41] | 79(2008)[18] | 7,020,048 |
| Ireland/Éire | 2,884,002(1966)[19] | 3,503,000(1990) [20] | 3,571,000 (1994)[16] | 3,840,838 (2000) | 4,470,700 [42] (2010) | 78 (2008)[18] | 1,586,698 |
| The PRC/China | 720,000,000(1967)[19] | 1,139,060,000(1990) [20] | 1,208,841,000 (1994)[16] | 1,286,975,468 (2004) | 1,339,724,852(2010)[43] | 73 (2008)[18] | 619,724,852 |
| Japan*** | 98,274,961(1965)[19] | 123,537,000(1990) [20] | 124,961,000 (1994)[16] | 127,333,002 (2002) | 127,420,000 (2010)[44] | 82(2008)[18] | 28,123,865 |
| Ryukyu Islands (Once occupied by the US)*** | 934,176(1965)[19] | — | — | — | — | — | — |
| India# | 511,115,000 (1967)[19] | 843,931,000 (1990) [20] | 918,570,000 (1994)[16] | 1,028,610,328 (2001) | 1,210,193,422(2011)[45] | 69 (2008)[18] | 699,078,422 |
Notes
* Eritrea left Ethiopia in 1991.
** Split into the nations of Sudan and Southern Sudan during 2011.
*** Merged in 1972.
# Merged in 1975.
- Into the future
Main article: Projections of population growth
The majority of world population growth today is occurring in less developed countries.
According to UN’s 2010 revision to its population projections, world population will peak at 10.1bn in 2100 compared to 7bn in 2011.[46] A 2014 paper by demographers from several universities and the United Nations Population Division forecast that the world’s population will reach about 10.9 billion in 2100 and continue growing thereafter.[47] However, some experts dispute the UN’s forecast and have argued that birthrates will fall below replacement rate in the 2020s. According to these forecasters, population growth will be only sustained till the 2040s by rising longevity but will peak below 9bn by 2050.[48]