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Research Note: Intergenerational Transmission Is Not Sufficient for Positive Long-Term Population Growth
Samuel Arenberg1, Kevin Kuruc2, Nathan Franz3
1National Bureau of Economic Research, Cambridge, MA, USA.
Demography
|October 19, 2022
Summary
Global population growth is projected to decline due to falling fertility rates. Even with intergenerational fertility transmission, long-term population growth is unlikely as higher-fertility groups also show declining birth rates, suggesting depopulation is plausible.
Area of Science:
- Demography
- Sociology
- Population Studies
Background:
- Global population projections indicate a continuing decline in fertility rates.
- Scholarly arguments suggest intergenerational fertility transmission could lead to positive long-term population growth.
- These arguments posit that higher-fertility parents influence their children's fertility, leading dominant groups to increase population size.
Purpose of the Study:
- To investigate whether intergenerational fertility transmission is sufficient to ensure positive long-term population growth.
- To analyze the empirical and theoretical factors influencing future population trends.
- To assess the likelihood of global depopulation under various fertility scenarios.
Main Methods:
- Analysis of long-term global population projections.
- Examination of intergenerational fertility transmission models.
- Quantitative assessment of fertility rates and transmission imperfections.
- Evaluation of fertility trends in high-fertility subpopulations.
Main Results:
- Intergenerational fertility transmission alone is insufficient to guarantee positive long-term population growth.
- Imperfect fertility transmission means higher-fertility parents may have too few children with sustained high fertility preferences.
- Even high-fertility subpopulations are experiencing declining fertility rates, often falling below replacement levels.
Conclusions:
- Long-term global depopulation is plausible, even under models incorporating fertility transmission.
- The primary driver remains the declining fertility rates across all subpopulations.
- Understanding the consequences of potential depopulation is crucial for future societal planning.
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