供稿：董全方, Article by Tiffany Dong, DLSPH, University of Toronto
According to data released by the National Bureau of Statistics in China on January 17, 2022, there were 9.56 million new births, 10.41 million deaths, a decrease of 850,000, and the natural growth rate was -0.60‰. The historic moment of population aging is coming sooner than expected. In October 2020, researchers from the University of Washington in the United States published a study in The Lancet, showing that the world’s population will reach a peak of 9.7 billion in 2064 and then drop to 8.8 billion in 2100. Asia, Central and Eastern Europe will become the regions with the fastest population shrinkage, and the populations of 23 countries and regions including China, Japan, South Korea and Italy will be reduced to half of their original population. In 2100, among the 195 countries and regions in the world, the total fertility rate of 83 countries will be lower than the fertility replacement level.
The low fertility level means that the number of children a couple has is less than 2, which is the most direct cause of lower population. In 2022, the total fertility rate of the global population was 2.428, which was 0.41% lower than that in 2021. According to the forecast of the United Nations Population Division, the world’s total fertility rate will continue to decline, falling to 2.194 by 2050 and 1.929 by 2100, which is far below the minimum fertility rate of 2.1 necessary to maintain the population replacement level. The figure below shows the trend of fertility and annual percentage change projected by the United Nations Population Division.
从全球人口生育率地区分布来看，亚洲、中欧和东欧将成为人口缩减速度最快的地区，中国、日本、韩国、意大利等23个国家和地区的人口数量将减少为原来的一半。来自《柳叶刀》2020年10月美国华盛顿大学研究团队的《Fertility, mortality, migration, and population scenarios for 195 countries and territories from 2017 to 2100: a forecasting analysis for the Global Burden of Disease Study》研究结果表明，非洲和阿拉伯将塑造人类的未来，而欧洲和亚洲由于人口轨迹的变化，影响力也逐渐减弱。到21世纪末，全球人口结构、经济发展结构、种族及民族分布或将迎来一个新的篇章。下图为2020-2025年全球生育率情况。
From the perspective of the regional distribution of the global population fertility rate, Asia, Central and Eastern Europe will become the regions with the fastest population aging, and the populations of 23 countries and regions including China, Japan, South Korea, and Italy will be reduced to half of their original population. The results of the study “Fertility, mortality, migration, and population scenarios for 195 countries and territories from 2017 to 2100: a forecasting analysis for the Global Burden of Disease Study” by the research team of the University of Washington in The Lancet in October 2020 shows that , Africa and Arabia will shape the future of population distribution, while Europe and Asia will gradually lose their influence due to changing population trajectories. By the end of the 21st century, the global population structure, economic development structure, and racial and ethnic distribution may usher in a new chapter. The figure below shows the prediction of global fertility rate from 2020 to 2025.
In terms of developed countries, the sharp decline in overall fertility rate and increasing life expectancy have become the main reasons for population aging. However, for many developing countries, the impact of the lower birth rate is the main cause of the severe population aging. The number of people over the age of 80 is expected to increase six-fold, from 141 million to 866 million, by 2100, according to the study by a University of Washington research team published in The Lancet. The ratio of the population over the age of 80 to the population under the age of 5 will exceed 2:1. The figure below shows the global population age structure in 2017 and 2100.
Many countries or regions have adopted similar countermeasures in response to the low fertility rate and population aging, which are mainly shown in four aspects: encouraging births, delaying retirement, guaranteeing old-age care, and immigrant compensation. From the perspective of policy objectives, these policy tools combinations attempt to form a joint force from the perspectives of reducing labor costs, increasing demand-side economic growth, easing the pressure on pension fiscal expenditures, and maintaining social and economic development, so as to fully relieve the pressure of population aging and shrinking labor force. Looking back at China and tracing back to the source, some problems such as the high commodity prices, high housing prices, the wealth distribution gap, the continued existence of the urban-rural dual structure, and the siphon effect of big cities, and the employment pressure will all flock to the population problem: “The gray rhinoceros is coming.”
列思泰赫和冯德卡(Lesthaeghe and Van de Kaa)共同提出了第二次人口转变理论（Second Demographic Transition，SDT），即在宏观层面，低生育率的形成与思想观念转变、社会经济发展变化和制度友好程度等有关。对于适龄者除了税收优惠和现金福利等经济补偿外，公共服务的提高、产假制度的完善、住房保障等对于鼓励生育至关重要。与此同时也要考虑老龄人口的生存状态，不能让那些为劳动力市场贡献一生老年人成为人口老龄化的牺牲品。纵观全球的生育低迷和部分发达国家的深度老龄化时代，促进人口地域流动，把人口交给市场，使需求和供给弹性化配适，也许是一个值得考虑的应对方案。
Lesthaeghe and Van de Kaa (Lesthaeghe and Van de Kaa) jointly proposed the second demographic transition theory (Second Demographic Transition, SDT), that is, at the macro level, the formation of low fertility rate is related to the transformation of ideas, social and economic development. The change is related to the friendliness of the system and so on. In addition to economic compensation such as tax incentives and cash benefits, the improvement of public services, the improvement of the maternity leave system, and housing security are crucial to encouraging childbearing. At the same time, we should consider the living quality of the aging population, and we cannot allow those who have dedicated their lives to the labor market to become victims of population aging. Looking at the global fertility downturn and the serious aging situation in some developed countries, it may be a solution worth considering to promote the geographical mobility of the population, hand over the population to the market, and make the demand and supply elastic in migration.
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