The Next 4 Billion People: The Demography and Economics of Population Growth in the 21st Century
Présenté par David Lam, Department of Economics and Population Studies Center, University of Michigan ; Discutant : Didier Blanchet (Insee)
The U.N. projects that world population will increase by 4 billion people – from 7 billion to 11 billion – between 2010 and 2100. Can the world support another 4 billion people? To answer this question it is useful to look back at the period 1960-2010, when the world also added 4 billion people. In spite of this rapid population growth, living standards improved between 1960 and 2010 almost everywhere in the world, with every major region experiencing rising per capita food production, declining rates of poverty, and rapid growth of education. The next 4 billion people will look quite different than the previous 4 billion, however. This lecture will explore the demographic and economic dimensions of these differences. One of the most surprising differences between 21st-century population growth and 20th-century population growth is that the projected number of children age 0-4 will actually decline between 2010 and 2100, in spite of the additional 4 billion people. While 20th-century population growth was dominated by growth of the youngest age groups, 21st-century population growth will be dominated by growth of older age groups. This lecture will discuss how it is possible to add 4 billion people to the world without adding any more children. It will also discuss the economic implications of this unusual pattern of population growth. While earlier population growth led to increased demand for schools and put pressure on youth unemployment, 21st century population growth will put pressure on the labor market for older workers and on support systems for the elderly. The lecture will also look at large regional differences in these patterns. While population growth will slow dramatically in most regions in the coming decades, sub-Saharan Africa will continue to experience rapid population growth and increasing numbers of young people. Africa will also experience an increase in the proportion of its population in working ages -- the only region that will do so -- a potentially positive factor in African economic growth.
David Lam is Director of the Institute for Social Research, Professor in the Department of Economics, and Research Professor in the Population Studies Center at the University of Michigan. He is Honorary Professor of Economics at the University of Cape Town, South Africa. He received a M.A. in demography and a Ph.D. in economics from the University of California, Berkeley. Professor Lam’s research focuses on the interaction of economics and demography in developing countries, including analysis of the economics of population growth, fertility, marriage, and aging. He has worked extensively in Brazil and South Africa, where his research analyzes links between education, labor markets, and income inequality. He has served as president of the Population Association of America and currently serves on the Council of the International Union for the Scientific Study of Population (IUSSP). He was a member of the Committee on Population of the U.S. National Academy of Sciences, and has served as an advisor or consultant to the World Bank, the U.S. National Institutes of Health, the United Nations Population Division, the United Nations Development Program, and the South Africa Office of the Presidency.