title: World population stabilization unlikely this century.
abstract: The United Nations (UN) recently released population projections based on data until 2012 and a Bayesian probabilistic methodology. Analysis of these data reveals that, contrary to previous literature, the world population is unlikely to stop growing this century. There is an 80% probability that world population, now 7.2 billion people, will increase to between 9.6 billion and 12.3 billion in 2100. This uncertainty is much smaller than the range from the traditional UN high and low variants. Much of the increase is expected to happen in Africa, in part due to higher fertility rates and a recent slowdown in the pace of fertility decline. Also, the ratio of working-age people to older people is likely to decline substantially in all countries, even those that currently have young populations.
authors.affiliation: Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA. gerland@un.org raftery@u.washington.edu.
authors.forename: Patrick
authors.initials: P
authors.lastname: Gerland
authors.affiliation: Departments of Statistics and Sociology, University of Washington, Seattle, WA 98195-4322, USA. gerland@un.org raftery@u.washington.edu.
authors.forename: Adrian E
authors.initials: AE
authors.lastname: Raftery
authors.affiliation: Center for Statistics and the Social Sciences, University of Washington, Seattle, WA 98195-4320, USA.
authors.forename: Hana
authors.initials: H
authors.lastname: Sevčíková
authors.affiliation: Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA.
authors.forename: Danan
authors.initials: D
authors.lastname: Gu
authors.affiliation: Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Spoorenberg
authors.affiliation: Department of Statistics and Applied Probability and Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117546.
authors.forename: Leontine
authors.initials: L
authors.lastname: Alkema
authors.affiliation: Department of Statistics, Colorado State University, Fort Collins, CO 80523-1877, USA.
authors.forename: Bailey K
authors.initials: BK
authors.lastname: Fosdick
authors.affiliation: James Cook University Singapore, 600 Upper Thomson Road, Singapore 574421.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Chunn
authors.affiliation: Institutional Research, University of Washington, Seattle, WA 98195-9445, USA.
authors.forename: Nevena
authors.initials: N
authors.lastname: Lalic
authors.affiliation: Latin American and Caribbean Demographic Center (CELADE), Population Division of the United Nations Economic Commission for Latin America and the Caribbean, Santiago, Chile.
authors.forename: Guiomar
authors.initials: G
authors.lastname: Bay
authors.affiliation: Population Division, United Nations, New York, NY, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Buettner
authors.affiliation: Population Division, United Nations, New York, NY, USA.
authors.forename: Gerhard K
authors.initials: GK
authors.lastname: Heilig
authors.affiliation: Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA.
authors.forename: John
authors.initials: J
authors.lastname: Wilmoth
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D006801:Humans; D008875:Middle Aged; D011158:Population Growth; D035501:Uncertainty; D014480:United Nations; D014937:Work; D055815:Young Adult