2018 World Population Data
CHANGING AGE STRUCTURES
The World Population Is Growing Older
With continued declines in fertility and mortality, the global population's shift toward an older age structure, known as population aging, will accelerate. Older adults' (ages 65+) share of the global population increased from 5 percent in 1960 to 9 percent in 2018 and is projected to rise to 16 percent by 2050, with the segment ages 85 and older growing the fastest. Children's (ages 0 to 14) share is falling, from 37 percent in 1960, to 26 percent in 2018, with a projected decrease to 21 percent by 2050.
What Is Demographic Transition?
Demographic transition is the long-term shift in birth and death rates from high to low levels in a population. The mortality decline usually precedes the fertility decline, resulting in rapid population growth during the transition period.
The demographic transition refers to the long-term change that populations undergo from high to low rates of births and deaths. It can be broadly divided into three phases. The first phase is characterized by declining mortality but continued high fertility, leading to rapid population growth and increases in the share of children in the population. Many countries in sub-Saharan Africa, such as Niger, Tanzania, and Democratic Republic of Congo, are in this first phase of transition.
The second phase is characterized by declining fertility and further declines in mortality. As smaller birth cohorts replace larger ones and larger birth cohorts age into adulthood, the share of children in the population begins to decline while the share of working-age adults grows. Many countries in Asia and Latin America and the Caribbean, such as India, Brazil, and the Dominican Republic, are in this second phase.
The third phase is characterized by low levels of both fertility and mortality, where the share of child and working-age populations declines and the share of older adults increases. Japan and most countries in Europe are in this final phase of the transition. The timing and speed of these age structure changes have important social and economic implications.
Each Population Age Structure Presents Different Challenges
Population age structure has implications for national policy agendas and resource allocation. Countries with relatively high fertility and child dependency face challenges in investing sufficient resources in the development of young people's human capital. If such investments are made, these countries have an opportunity to reap the economic growth benefits of a larger, better-educated working-age population. Countries experiencing high old-age dependency or double dependency (relatively large shares of child and older-adult populations) face different challenges. They must address the high costs of older adults' medical and long-term care needs while also investing in the well-being of and future opportunities for younger generations. By monitoring and projecting age structure shifts, countries can better plan to meet the needs of their populations.
What Is a Dependency Ratio?
A dependency ratio is the number of people in a dependent age group (those under age 15 or ages 65 and older) divided by the number in the working-age group (ages 15 to 64), multiplied by 100. For instance, a child dependency ratio of 45 means there are 45 children for every 100 working-age individuals.
PRB has grouped countries into five age dependency categories based on the combination of child and old-age dependency ratios in each country. These category definitions used in the map below are based on the average child and old-age dependency ratios for the world in 2018, as well as the overall distribution of countries by these ratios in 2018. The 2050 map applies the 2018-based category definitions to the projected dependency ratios in 2050.
AGE DEPENDENCY CATEGORIES
View maps of countries’ age dependency categories for 2018 (estimated) and 2050 (projected).
HIGH CHILD DEPENDENCY
High child dependency ratio (>45) and low old-age dependency ratio (<15).
MODERATE CHILD DEPENDENCY
Moderate child dependency ratio (29-45) and low old-age dependency ratio (<15).
Moderate child dependency ratio (29-45) and high old-age dependency ratio (≥15).
HIGH OLD-AGE DEPENDENCY
Low child dependency ratio (<29) and high old-age dependency ratio (≥15).
LOW OVERALL DEPENDENCY
Low child dependency ratio (<29) and low old-age dependency ratio (<15).
Investments in education are critical to ensuring that a country has a skilled workforce. When the share of a country’s young dependent population (ages 0 to 14) decreases relative to the working-age population (ages 15 to 64), and adequate jobs exist for the working-age population, per capita income increases, making more resources available for investments in the health and education of […]READ FULL STORY
For countries with a large share of young people ages 0 to 14, investment in upper-secondary education is critical to developing the skilled workforce needed to accelerate economic growth.SHARE ON TWITTER
A country’s age structure and its socioeconomic and political contexts can influence the labor force participation rate (LFPR) of older adults. At the same time, old-age LFPR can impact countries’ policies and social support structures. Rates vary considerably by country. Overall, they tend to be higher in countries in the high and moderate child dependency categories. However, many countries in […]READ FULL STORY
Older adults’ labor force participation tends to be higher in countries in the high and moderate child dependency categories, but older men’s labor force participation has decreased in many of these countries.SHARE ON TWITTER
The poverty rate is one important indicator of economic well-being that varies widely across age groups. In the mid-1960s, 29 percent of U.S. adults ages 65 and older lived in poverty, compared with 18 percent of children under age 18. However, the trends in poverty rates for these two age groups have diverged markedly since 1974, with the rate among older adults decreasing, and the rate among […]READ FULL STORY
Investing resources today to reduce poverty among children can increase their future productive capacity and help to offset the costs of an aging population.SHARE ON TWITTER
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