World population estimates

This article lists estimates of world population over the course of history and prehistory, as well as projections of future developments. In summary, estimates for the progression of world population since the late medieval period are in the following ranges:

year	1400	1500	1600	1700	1800	1900	2000
population (in millions)	350–400	425–500	500–580	600–680	890–980	1,560–1,710	6,060–6,150

Estimates for pre-modern times are necessarily fraught with great uncertainties, and few of the published estimates have confidence intervals; in the absence of a straightforward means to assess the error of such estimates, a rough idea of expert consensus can be gained by comparing the values given in independent publications. Population estimates cannot be considered accurate to more than two decimal digits; for example, world population for the year 2012 was estimated at 7.02, 7.06 and 7.08 billion by the United States Census Bureau, the Population Reference Bureau and the United Nations Department of Economic and Social Affairs, respectively, corresponding to a spread of estimates of the order of 0.8%.

Deep prehistory

Most published estimates of historical world population begin at "year zero" of the Common Era, when world population was in the nine digits (estimates range between 150 and 330 million).

Some estimates extend their timeline into deep prehistory, to "10,000 BC", i.e. the last glacial maximum,^[1] when world population estimates range roughly between one and ten million.

Estimates for yet deeper prehistory, into the Upper Paleolithic, are of a different nature. At this time human populations consisted entirely of non-sedentary hunter-gatherer populations, which fall into a number of archaic species or sub-species, some but not all of which may be ancestral to the modern human population due to possible archaic human admixture with modern humans taking place during the Upper Paleolithic. Estimates of the size of these populations are a topic of paleoanthropology. A late human population bottleneck is postulated by some scholars at approximately 70,000 years ago, during the Toba catastrophe, when the Homo sapiens population may have dropped to as low as between 1,000 and 10,000 individuals.^[2][3][4]

For the time of speciation of Homo sapiens, ca. 130,000 years ago, Sjödin et al. (2012) estimate an effective population size of the order of 10,000 to 30,000 individuals, inferring an actual "census population" of early Homo sapiens of roughly 100,000 to 300,000 individuals.^[5]

Historical population

The following table uses astronomical year numbering for dates, negative numbers corresponding roughly to the corresponding year BC (i.e. -10000 = 10,001 BC, etc.). The table starts counting around the Late Glacial Maximum period, in which ice retreated and humans started to spread into the northern hemisphere.

Before 1950

Year	Population Reference Bureau (1973–2015)[6]	United Nations Department of Economic and Social Affairs (2015)[7]	Maddison (2008)[8]	HYDE (2007)[9]	Tanton (1994)[10]	Biraben (1980)[11]	McEvedy & Jones (1978)[12]	Thomlinson (1975)[13]	Durand (1974)[14]	Clark (1967)[15]
-10000				2M			4M	1–10M
-9000				4M
-8000	5M			5M					5–10M
-7000				8M
-6000				11M
-5000				18M			5M	5–20M
-4000				28M			7M
-3000				45M			14M
-2000				72M			27M
-1000				115M			50M
-200							150M
0	300M	300M	231M[16]	188M	150M	255M	170M	200M	270–330M	256M[17]
100	300M			195M
200	300M			202M		256M	190M
300	300M			205M
350										254M
400	300M			209M		206M	190M
500	280M			210M		206M	190M
600	300M			213M		206M	200M			237M
700	310M			226M		207M	210M
800	330M			240M		224M	220M			261M
900	360M			269M		226M	240M
1000	400M	310M	267M	295M		254M	265M		275–345M	280M
1100				353M		301M	320M
1200	450M			393M		400M	360M			384M
1250		400M				416M
1300	500M			392M	300M	432M	360M	400M
1340						443M				378M
1400	440M			390M		374M	350M
1500	500M	500M	438M	461M	460M	425M			440–540M	427M
1600	660M		556M	554M		579M	545M			498M
1650	500M						545M	500M		516M
1700	760M		603M	603M	600M	679M	610M	600M		641M
1750	795M	791M		814M		770M	720M	700M	735–805M	731M
1800	1,000M	978M		989M	900M	954M	900M	900M		890M
1820			1,042M
1850	1,265M	1,262M		1,263M		1,241M	1,200M	1,200M
1870			1,276M
1875							1,325M
1900	1,656M	1,650M	1,563M	1,654M	1,600M	1,633M	1,625M	1,600M	1,650–1,710M	1,668M
1910		1,750M		1,777M
1913			1,793M
1920		1,860M	1,863M	1,912M						1,968M
1925							2,000M
1930		2,070M		2,092M						2,145M
1940		2,300M	2,299M	2,307M						2,340M

1950 to present

For times after World War II, demographic data of some accuracy becomes available for a significant number of countries, and population estimates are often given as grand totals of numbers (typically given by country) of widely diverging accuracies. Some sources give these numbers rounded to the nearest million or the nearest thousand, while others give them without any rounding. Taking these numbers at face value would be false precision; in spite of being stated to four, seven or even ten digits, they should not be interpreted as accurate to more than three digits at best.

Year	United States Census Bureau (2015)[18]	Population Reference Bureau (1973–2015)[6]	United Nations Department of Economic and Social Affairs (2015)[7]	Maddison (2008)[8]	HYDE (2007)[9]	Tanton (1994)[10]	Biraben (1980)[11]	McEvedy & Jones (1978)[12]	Thomlinson (1975)[13]	Durand (1974)[14]	Clark (1967)[15]
1950	2,557,628,654	2,516,000,000	2,525,149,000	2,544,000,000	2,527,960,000	2,400,000,000	2,527,000,000	2,500,000,000	2,400,000,000		2,486,000,000
1951	2,594,939,877		2,572,850,917	2,571,663,000
1952	2,636,772,306		2,619,292,068	2,617,949,000
1953	2,682,053,389		2,665,865,392	2,665,959,000
1954	2,730,228,104		2,713,172,027	2,716,927,000
1955	2,782,098,943		2,761,650,981	2,769,074,000
1956	2,835,299,673		2,811,572,031	2,822,502,000
1957	2,891,349,717		2,863,042,795	2,879,934,000
1958	2,948,137,248		2,916,030,167	2,939,254,000
1959	3,000,716,593		2,970,395,814	2,995,909,000
1960	3,043,001,508		3,026,002,942	3,041,507,000	3,042,000,000
1961	3,083,966,929		3,082,830,266	3,082,161,000
1962	3,140,093,217		3,141,071,531	3,135,787,000							3,036,000,000
1963	3,209,827,882		3,201,178,277	3,201,354,000
1964	3,281,201,306		3,263,738,832	3,266,477,000
1965	3,350,425,793		3,329,122,479	3,333,138,000
1966	3,420,677,923		3,397,475,247	3,402,224,000							3,288,000,000
1967	3,490,333,715		3,468,521,724	3,471,464,000
1968	3,562,313,822		3,541,674,891	3,543,086,000
1969	3,637,159,050		3,616,108,749	3,615,743,000
1970	3,712,697,742		3,691,172,616	3,691,157,000	3,710,000,000		3,637,000,000		3,600,000,000	3,600,000,000– 3,700,000,000	3,632,000,000
1971	3,790,326,948		3,766,754,345	3,769,818,000
1972	3,866,568,653		3,842,873,611	3,846,499,000
1973	3,942,096,442		3,919,182,332	3,922,793,000	3,923,000,000						3,860,000,000
1974	4,016,608,813		3,995,304,922	3,997,677,000
1975	4,089,083,233		4,071,020,434	4,070,671,000				3,900,000,000	4,000,000,000
1976	4,160,185,010		4,146,135,850	4,141,445,000
1977	4,232,084,578		4,220,816,737	4,213,539,000
1978	4,304,105,753		4,295,664,825	4,286,317,000
1979	4,379,013,942		4,371,527,871	4,363,144,000
1980	4,451,362,735		4,449,048,798	4,439,529,000	4,461,000,000
1981	4,534,410,125		4,528,234,634	4,514,838,000
1982	4,614,566,561		4,608,962,418	4,587,307,000
1983	4,695,736,743		4,691,559,840	4,676,388,000
1984	4,774,569,391		4,776,392,828	4,756,521,000
1985	4,856,462,699		4,863,601,517	4,837,719,000		5,000,000,000
1986	4,940,571,232		4,953,376,710	4,920,968,000
1987	5,027,200,492		5,045,315,871	5,006,672,000
1988	5,114,557,167		5,138,214,688	5,093,306,000
1989	5,201,440,110		5,230,000,000	5,180,540,000
1990	5,288,955,934		5,320,816,667	5,269,029,000	5,308,000,000
1991	5,371,585,922		5,408,908,724	5,351,922,000
1992	5,456,136,278		5,494,899,570	5,435,722,000
1993	5,538,268,316		5,578,865,109	5,518,127,000
1994	5,618,682,132		5,661,086,346	5,599,396,000
1995	5,699,202,985	5,760,000,000	5,741,822,412	5,681,575,000
1996	5,779,440,593		5,821,016,750	5,762,212,000
1997	5,857,972,543	5,840,000,000	5,898,688,337	5,842,122,000
1998	5,935,213,248		5,975,303,657	5,921,366,000
1999	6,012,074,922		6,051,478,010	5,999,622,000
2000	6,088,571,383	6,067,000,000	6,127,700,428	6,076,558,000	6,145,000,000			5,750,000,000
2001	6,165,219,247	6,137,000,000	6,204,147,026	6,154,791,000
2002	6,242,016,348	6,215,000,000	6,280,853,817	6,231,704,000
2003	6,318,590,956	6,314,000,000	6,357,991,749	6,308,364,000
2004	6,395,699,509	6,396,000,000	6,435,705,595	6,374,056,000
2005	6,473,044,732	6,477,000,000	6,514,094,605	6,462,987,000
2006	6,551,263,534	6,555,000,000	6,593,227,977	6,540,214,000
2007	6,629,913,759	6,625,000,000	6,673,105,937	6,616,689,000
2008	6,709,049,780	6,705,000,000	6,753,649,228	6,694,832,000
2009	6,788,214,394	6,809,972,000	6,834,721,933	6,764,086,000
2010	6,866,332,358	6,892,319,000	6,916,183,482
2011	6,944,055,583	6,986,951,000	6,997,998,760
2012	7,022,349,283	7,057,075,000	7,080,072,417
2013	7,101,027,895	7,136,796,000	7,162,119,434
2014	7,178,722,893	7,238,184,000	7,243,784,000
2015	7,256,490,011	7,336,435,000	7,349,472,000

Projections

World population estimates from 1800 to 2100, based on "high", "medium" and "low" United Nations projections in 2010 (colored red, orange and green) and US Census Bureau historical estimates (in black). Actual recorded population figures (as of 2010) are colored in blue. According to the highest estimate, the world population may rise to 16 billion by 2100; according to the lowest estimate, it may decline to 6 billion.

As of 2015, the population of the world is projected to reach 8 billion in 2025, and 9 billion by about 2040/42. Kapitza (1996) estimated an asymptotic limit of population growth of 14 billion, 90% of which (12.6 billion) expected to be reached by 2135.^[19]

Reasonable predictions of population development are possible for the next 30 years or so, representing the period of fertility of the children alive today. Projections of population reaching more than one generation into the future are highly speculative: Thus, the United Nations Department of Economic and Social Affairs report of 2004 projected the world population to peak at 9.22 billion in 2075 and then stabilise at a value close to 9 billion;^[20] By contrast, a 2014 projection by the United Nations Population Division predicts a population close to 11 billion by 2100 without any declining trend in the foreseeable future.^[21] On the other hand, a conservative scenario published in 2012 assumes that a maximum of 8 billion will be reached before 2040.^[22]

The following table shows projections of world population for the 21st century.

Year	United States Census Bureau (2015)[18]	Population Reference Bureau (1973-2015)[6]	United Nations Department of Economic and Social Affairs (2015)[7]
2016	7,334,771,614		7,432,663,280
2017	7,412,778,971
2018	7,490,427,640
2019	7,567,402,977
2020	7,643,402,123		7,758,157,000
2021	7,718,256,830
2022	7,792,021,317
2023	7,864,725,370
2024	7,936,271,554
2025	8,006,580,553	8,000,000,000	8,141,661,000
2026	8,075,716,000
2027	8,143,729,466
2028	8,210,559,895
2029	8,276,190,519
2030	8,340,606,590	8,505,000,000	8,500,766,000
2031	8,403,880,343
2032	8,466,094,022
2033	8,527,246,205
2034	8,587,325,154
2035	8,646,304,704		8,838,908,000
2036	8,704,239,274
2037	8,761,189,197
2038	8,817,138,785
2039	8,872,066,537
2040	8,925,949,679		9,157,234,000
2041	8,978,822,945
2042	9,030,723,366
2043	9,081,617,002
2044	9,131,462,326
2045	9,180,225,214		9,453,892,000
2046	9,227,935,007
2047	9,274,616,811
2048	9,320,232,984
2049	9,364,750,182
2050	9,408,141,302	9,804,000,000	9,725,148,000
2055			9,968,809,000
2060			10,184,290,000
2065			10,375,719,000
2070			10,547,989,000
2075			10,701,653,000
2080			10,836,635,000
2085			10,953,525,000
2090			11,055,270,000
2095			11,142,461,000
2100			11,213,317,000

Other, historical projections include

• Tanton (1994):^[10] 8 billion for the year 2020;
• McEvedy & Jones (1978):^[12] 5.75 billion for the year 2000, 8.25 billion for the year 2200.

By world region

Population estimates for world regions based on Maddison (2007),^[23] in millions. The row showing total world population includes the average growth rate per year over the period separating each column from the preceding one.

year	0	1000	1500	1600	1700	1820	1913	2000	2030
East/Southeast Asia	74 (33%)	88 (33%)	156 (28%)	223 (37%)	216 (36%)	469 (45%)	613 (34%)	1,996 (33%)	2,417 (30%)
South Asia	75 (33%)	75 (28%)	110 (25%)	135 (24%)	165 (27%)	216 (21%)	326 (18%)	1,372 (23%)	2,003 (25%)
Europe[24]	34 (15%)	40 (15%)	78 (18%)	112 (20%)	127 (21%)	224 (21%)	498 (28%)	742 (13%)	829 (11%)
West Asia	19 (8%)	20 (7%)	18 (3%)	21 (3%)	21 (3%)	25 (2%)	39 (2%)	237 (4%)	370 (5%)
Africa	17 (8%)	32 (12%)	47 (11%)	55 (10%)	61 (10%)	74 (7%)	125 (7%)	798 (13%)	1,449 (18%)
South/Central America	6 (3%)	11 (4%)	18 (4%)	9 (2%)	12 (2%)	22 (2%)	81 (5%)	520 (9%)	702 (9%)
North America	1 (0%)	1 (0%)	2 (0%)	2 (0%)	1 (0%)	11 (1%)	105 (6%)	314 (5%)	413 (5%)
World	226	267 (+ 0.02% p.a.)	438 (+ 0.1% p.a.)	556 (+ 0.2% p.a.)	603 (+ 0.1% p.a.)	1,041 (+ 0.5% p.a.)	1,791 (+ 0.6% p.a.)	6,062 (+ 1.4% p.a.)	8,175 (+ 1.0% p.a.)

See also

• Projections of population growth
• Population growth

References

1. Pala, M; Olivieri, A; Achilli, A; Accetturo, M; Metspalu, E; Reidla, M; Tamm, E; Karmin, M; Reisberg, T; Hooshiar Kashani, B; Perego, UA; Carossa, V; Gandini, F; Pereira, JB; Soares, P; Angerhofer, N; Rychkov, S; Al-Zahery, N; Carelli, V; Sanati, MH; Houshmand, M; Hatina, J; Macaulay, V; Pereira, L; Woodward, SR; Davies, W; Gamble, C; Baird, D; Semino, O; Villems, R; Torroni, A; Richards, MB (2012). "Mitochondrial DNA signals of late glacial recolonization of Europe from near eastern refugia". Am. J. Hum. Genet. 90: 915–24. doi:10.1016/j.ajhg.2012.04.003. PMC 3376494. PMID 22560092.
2. Stanley H. Ambrose (1998). "Late Pleistocene human population bottlenecks, volcanic winter, and differentiation of modern humans". Journal of Human Evolution. 34 (6): 623–651. doi:10.1006/jhev.1998.0219. PMID 9650103.
3. Ambrose, Stanley H. (2005). "Volcanic Winter, and Differentiation of Modern Humans". Bradshaw Foundation. Retrieved 2006-04-08.
4. Robock, A., C.M. Ammann, L. Oman, D. Shindell, S. Levis, and G. Stenchikov (2009). "Did the Toba volcanic eruption of ~74k BP produce widespread glaciation?". Journal of Geophysical Research. 114 (D10): D10107. Bibcode:2009JGRD..11410107R. doi:10.1029/2008JD011652.
5. Per Sjödin, Agnès E Sjöstrand, Mattias Jakobsson and Michael G B Blum, "Resequencing data provide no evidence for a human bottleneck in Africa during the penultimate glacial period" Mol Biol Evol (2012) doi: 10.1093/molbev/mss061. "A small human effective population size, on the order of 10,000 individuals, which is smaller than the effective population size of most great apes, has been interpreted as a result of a very long history, starting ∼ 2 mya, of a small population size, coined as the long-necked bottle model (Harpending et al. 1998; Hawks et al. 2000). Our findings are consistent with this hypothesis, but, depending on the mutation rate, we find either an effective population size of NA = 12,000 (95% C.I. = 9,000−15,500 when averaging over all three demographic models) using the mutation rate calibrated with the human-chimp divergence or an effective population size of NA = 32,500 individuals (95% C.I. = 27,500−34,500) using the mutation rate given by whole-genome trio analysis (The 1000 Genomes Project Consortium 2010) (supplementary figure 4 and table 6, Supplementary Material online). Not surprisingly, the estimated effective mutation rates θ = 4NAµ are comparable for the two mutation rates we considered, and are equal to 1.4 × 10⁻³/bp/generation (95% C.I. = (1.1−1.7) × 10⁻³). Relating the estimated effective population size to the census population size during the Pleistocene is a difficult task because there are many factors affecting the effective population size (Charlesworth 2009). Nevertheless, based on published estimates of the ratio between effective and census population size, a comprehensive value on the order of 10% has been found by Frankham (1995). This 10% rule roughly predicts that 120,000−325,[0]00 individuals (depending on the assumed mutation rate)"
6. Data from Population Reference Bureau.
   2015 estimate: (a) Toshiko Kaneda, 2015, "2015 World Population Data Sheet".
   2014 estimate: (b) Carl Haub, 2014, "2014 World Population Data Sheet".
   2013 estimate: (c) Carl Haub, 2013, "2013 World Population Data Sheet".
   2012 estimate: (d) Carl Haub, 2012, "2012 World Population Data Sheet".
   2011 estimate: (e) Carl Haub, 2011, "2011 World Population Data Sheet".
   2010 estimate: (f) Carl Haub, 2010, "2010 World Population Data Sheet".
   2009 estimate: (g) Carl Haub, 2009, "2009 World Population Data Sheet".
   2008 estimate: (h) Carl Haub, 2008, "2008 World Population Data Sheet".
   2007 estimate: (i) Carl Haub, 2007, "2007 World Population Data Sheet".
   2006 estimate: (j) Carl Haub, 2006, "2006 World Population Data Sheet".
   2005 estimate: (k) Carl Haub, 2005, "2005 World Population Data Sheet".
   2004 estimate: (l) Carl Haub, 2004, "2004 World Population Data Sheet".
   2003 estimate: (m) Carl Haub, 2003, "2003 World Population Data Sheet".
   2002 estimate: (n) Carl Haub, 2002, "2002 World Population Data Sheet".
   2001 estimate: (n) Carl Haub, 2001, "2001 World Population Data Sheet".
   2000 estimate: (p) 2000, "9 Billion World Population by 2050".
   1997 estimate: (q) 1997, "Studying Populations".
   Estimates for 1995 and prior: (r) Carl Haub, 1995, "How Many People Have Ever Lived on Earth?" Population Today, Vol. 23 (no. 2), pp. 5–6.
7. Data from United Nations Department of Economic and Social Affairs, Population Division.
   1950–2100 estimates (only medium variants shown): (a) World Population Prospects: The 2008 Revision.
   Estimates prior to 1950: (b) "The World at Six Billion", 1999.
   Estimates from 1950 to 2100: (c) "Population of the entire world, yearly, 1950 - 2100", 2013.
   2014: (d) http://esa.un.org/unpd/wup/Highlights/WUP2014-Highlights.pdf "2014 World Urbanization Prospects", 2014.]
   2015: (e) http://esa.un.org/unpd/wpp/Publications/Files/Key_Findings_WPP_2015.pdf "2015 World Urbanization Prospects", 2015.] Archived March 20, 2014, at the Wayback Machine.
8. Angus Maddison, 2003, The World Economy: Historical Statistics, Vol. 2, OECD, Paris ISBN 92-64-10412-7.
   "Statistical Appendix" (2008, ggdc.net) "The historical data were originally developed in three books: Monitoring the World Economy 1820-1992, OECD, Paris 1995; The World Economy: A Millennial Perspective, OECD Development Centre, Paris 2001; The World Economy: Historical Statistics, OECD Development Centre, Paris 2003. All these contain detailed source notes. Figures for 1820 onwards are annual, wherever possible. For earlier years, benchmark figures are shown for 1 AD, 1000 AD, 1500, 1600 and 1700." "OECD countries GDP revised and updated 1991-2003 from National Accounts for OECD Countries, vol. I, 2006. Norway 1820-1990 GDP from Ola Grytten (2004), “The Gross Domestic Product for Norway, 1830-2003” in Eitrheim, Klovland and Qvigstad (eds), Historical Monetary Statistics for Norway, 1819-2003, Norges Bank, Oslo. Latin American GDP 2000-2003 revised and updated from ECLAC, Statistical Yearbook 2004 and preliminary version of the 2005 Yearbook supplied by Andre Hofman. For Chile, GDP 1820-2003 from Rolf Lűders (1998), “The Comparative Economic Performance of Chile 1810-1995”, Estudios de Economia, vol. 25, no. 2, with revised population estimates from Diaz, J., R. Lűders, and G. Wagner (2005) Chili 1810-2000: la Republica en Cifras, mimeo, Instituto de Economia, Universidad Católica de Chile. For Peru, GDP 1896-1990 and population 1896-1949 from Bruno Seminario and Arlette Beltran, Crecimiento Economico en el Peru 1896-1995, Universidad del Pacifico, 1998. " "For Asia there are amendments to the GDP estimates for South and North Korea, 1911-74, to correct an error in Maddison (2003). Estimates for the Philippines, 1902-1940 were amended in line with Richard Hooley (2005), 'American Economic Policy in the Philippines, 1902-1940', Journal of Asian Economics, 16. 1820 estimates were amended for Hong Kong, the Philippines, Singapore, Sri Lanka, Taiwan and Thailand." "Asian countries GDP revised and updated 1998-2003 from Asian Development Bank, Key Indicators 2005, except for South Korea and Japan, where OECD sources were used for 1991-2003. GDP for African countries updated 2000-2003 from IMF, World Economic Outlook, April 2005. Population estimates for all countries except China and Indonesia revised and updated 1950-2008 and 2030 from International Data Base, International Programs Center, Population Division, US Bureau of the Census, April 2005 version. China’s population 1990-2003 from China Statistical Yearbook 2005, China Statistics Press, Beijing. Indonesian population 1950-2003 kindly supplied by Pierre van der Eng. The figures now include three countries previously omitted: Cook Islands, Nauru and Tuvalu."
9. Data from History Database of the Global Environment. K. Klein Goldewijk and G. van Drecht, "HYDE 3.1: Current and historical population and land cover", in Eds. A. F. Bouwman, T. Kram, and K. Klein Goldewijk, "Integrated modelling of global environmental change. An overview of IMAGE 2.4", Netherlands Environmental Assessment Agency (MNP), Bilthoven, The Netherlands.
10. John H. Tanton, 1994, "End of the Migration Epoch? Time For a New Paradigm", The Social Contract, Vol. 4 (no 3), pp. 162–173.
11. Slightly updated data from original paper in French: (a) Jean-Noël Biraben, 1980, "An Essay Concerning Mankind's Evolution", Population, Selected Papers, Vol. 4, pp. 1–13. Original paper in French: (b) Jean-Noël Biraben, 1979, "Essai sur l'évolution du nombre des hommes", Population, Vol. 34 (no. 1), pp. 13–25.
12. Colin McEvedy and Richard Jones, 1978, Atlas of World Population History, Facts on File, New York, ISBN 0-7139-1031-3.
13. Ralph Thomlinson, 1975, Demographic Problems: Controversy over population control, 2nd Ed., Dickenson Publishing Company, Ecino, CA, ISBN 0-8221-0166-1.
14. John D. Durand, 1974, "Historical Estimates of World Population: An Evaluation", University of Pennsylvania, Population Center, Analytical and Technical Reports, Number 10.
15. Colin Clark, 1967, Population Growth and Land Use, St. Martin's Press, New York, ISBN 0-333-01126-0.
16. "The present figures are a revision and update of those presented on this website in 2003. The most significant changes are in the entries for the year 1, where gaps in previous tables have been filled with the new estimates for the Roman Empire in Maddison (2007). The estimates are in fact for 14 AD"
17. The estimates are in fact for 14 AD"
18. Data from U.S. Census Bureau, International Data Base Retrieved on June 10, 2014
19. "The expression for growth (6) indicates a limit for world population N=πK²=14×10⁹, in the foreseeable future. Of this asymptotic limit 90% will be reached for Model III by year 2135, or in 3T years after T1 = 2007." Sergei P. Kapitza, 'The phenomenological theory of world population growth', Physics-Uspekhi 39(1) 57-71 (1996).
20. United Nations Department of Economic and Social Affairs. World Population to 2300. 2004. Executive Summary, Page 2.
21. Gerland, P.; Raftery, A. E.; Ev Ikova, H.; Li, N.; Gu, D.; Spoorenberg, T.; Alkema, L.; Fosdick, B. K.; Chunn, J.; Lalic, N.; Bay, G.; Buettner, T.; Heilig, G. K.; Wilmoth, J. (September 14, 2014). "World population stabilization unlikely this century". Science. AAAS. 346 (6206): 234–7. doi:10.1126/science.1257469. ISSN 1095-9203. PMC 4230924. PMID 25301627. Retrieved September 21, 2014.
22. Randers, Jorgen (2012). 2052: A Global Forecast for the Next Forty Years. Vermont: Chelsea Green Publishing. p. 62.
23. Angus Maddison, The World Economy: Historical Statistics, Statistical Appendix (2007, ggdc.net). Estimates cited are for the beginning of the 1st millennium ("year 0"), the beginning of the 2nd millennium ("year 1000"), and for the beginning each century since the 16th (years 1820 and 1913 are given for the 19th and 20th century, respectively, as Maddison presents detailed estimates for these years), and a projection for the year 2030.
24. includes Central Asia (listed under "former USSR")

Further reading

• Haub, Carl (October 2011). "How Many People Have Ever Lived on Earth?". Population Reference Bureau. Retrieved 21 July 2013.

External links

• Historical Estimates of World Population—United States Census Bureau
• World Population Estimation Graps 10000 BC - 1950 AD World population estimation graphs; estimations by HYDE, Colin McEvedy, Massimo Livi Bacci