{"title":"The Formal Demography of Peak Population.","authors":"Joshua R Goldstein, Thomas Cassidy","doi":"10.1215/00703370-11216714","DOIUrl":null,"url":null,"abstract":"<p><p>When will the human population peak? In this article, we build on classical results by Ansley Coale, who showed that when fertility declines steadily, births reach their maximum before fertility reaches replacement level, and the decline in total population size does not occur until several decades after fertility has reached that level. We extend Coale's results by modeling longevity increases, net immigration, and a slowdown in fertility decline that resembles current projections. With these extensions, our models predict a typical lag between replacement-level fertility and population decline of about 35 to 40 years, consistent with projections by the United Nations and about 15 years longer than the lag predicted by Coale. Our analysis helps reveal underlying factors in the timing of peak population.</p>","PeriodicalId":48394,"journal":{"name":"Demography","volume":" ","pages":"419-438"},"PeriodicalIF":3.6000,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Demography","FirstCategoryId":"90","ListUrlMain":"https://doi.org/10.1215/00703370-11216714","RegionNum":1,"RegionCategory":"社会学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"DEMOGRAPHY","Score":null,"Total":0}
引用次数: 0
Abstract
When will the human population peak? In this article, we build on classical results by Ansley Coale, who showed that when fertility declines steadily, births reach their maximum before fertility reaches replacement level, and the decline in total population size does not occur until several decades after fertility has reached that level. We extend Coale's results by modeling longevity increases, net immigration, and a slowdown in fertility decline that resembles current projections. With these extensions, our models predict a typical lag between replacement-level fertility and population decline of about 35 to 40 years, consistent with projections by the United Nations and about 15 years longer than the lag predicted by Coale. Our analysis helps reveal underlying factors in the timing of peak population.
期刊介绍:
Since its founding in 1964, the journal Demography has mirrored the vitality, diversity, high intellectual standard and wide impact of the field on which it reports. Demography presents the highest quality original research of scholars in a broad range of disciplines, including anthropology, biology, economics, geography, history, psychology, public health, sociology, and statistics. The journal encompasses a wide variety of methodological approaches to population research. Its geographic focus is global, with articles addressing demographic matters from around the planet. Its temporal scope is broad, as represented by research that explores demographic phenomena spanning the ages from the past to the present, and reaching toward the future. Authors whose work is published in Demography benefit from the wide audience of population scientists their research will reach. Also in 2011 Demography remains the most cited journal among population studies and demographic periodicals. Published bimonthly, Demography is the flagship journal of the Population Association of America, reaching the membership of one of the largest professional demographic associations in the world.