s birth rates remain low and Athe median age rises, most developed and many emerging improvements through an increased share of economies will see their working age adults in the population, more female participation in the workforce, and populations peak and then start increased social stability associated with older cohorts. However, shifting age structures will to shrink by 2040. challenge some governments, including some developing countries that are aging before reaching higher incomes, such as China and Eastern Europe, and poor countries with surg- ing youth cohorts that will struggle to build su昀케cient infrastructure. Older Populations. Rising old-age dependen- SLOWING POPULATION GROWTH, cy ratios—the population age 65 and older AGING POPULATIONS relative to the working-age population—can weigh on growth even with adaptive strate- During the next 20 years, the world’s popu- gies, such as automation and increased immi- lation will continue to increase every year, gration. In many older countries, including a adding approximately 1.4 billion people to number of advanced economies, the cohort reach an estimated 9.2 billion by 2040, but over 65 is likely to approach 25 percent of the rate of population growth will slow in all the total population by 2040, up from only 15 regions. Population growth in most of Asia will percent as recently as 2010. Japan and South decline quickly, and after 2040, the population Korea are likely to reach median ages of more will begin to contract. Although India’s pop- than 53 in 2040, up from 48 and 44 respec- ulation growth is slowing, it will still overtake tively. Europe is not far behind with a project- China as the world’s most populous country ed average median age of 47, and Greece, around 2027. As birthrates remain low and Italy, and Spain are likely to age faster. These the median age rises, most developed and a countries are likely to see further productivity handful of emerging economies will see their slowdown in the coming decades because populations peak and then start to shrink by older workers usually show fewer productivity 2040, including China, Japan, Russia, and many gains and a greater share of national income European countries. In contrast, Sub-Saha- will be diverted to pensions and health care ran Africa will account for around two-thirds for seniors. of global population growth and is poised to Working Age Populations. Countries with nearly double its current population by 2050, portending extensive strains on infrastructure, large working-age cohorts and relatively few education, and healthcare. young and old dependents have the potential for higher household savings that can be di- Aging: An Opportunity and a Burden rected to investment in human development. The combination of fewer children per woman During the next 20 years, South Asia, Latin and people living longer will see the global America, and the Middle East and North Africa population age rise from a median of about will be in this window of high working-age 31 years in 2020 to 35 in 2040. In middle-in- populations relative to below-working-age come countries, falling birthrates and older and retired dependents. Sixty-eight percent populations can facilitate human development of South Asia’s population will be of working 18 GLOBAL TRENDS 2040