The world’s median age

The weekly quiz is provided by the Globalist, a daily online feature service that covers issues and trends in globalization. The nonpartisan organization provides commercial services and nonprofit educational features.

Question

While some regions of the world are grappling with the social and economic challenges of a “youth bulge,” other regions are facing the challenges of an aging population. We wonder: What is the median age of all the people alive on earth today?

A19.4 is not correct: The median age of all people living on the continent of Africa is 19.4 years, as of the UN Population Division’s 2015 estimate.

This puts the median age in Africa today at about the level of Asia’s back in 1970. (Asia’s has since risen to 30.3 years currently.)

There are two major factors explaining the very low median age in Africa. The first is the ongoing effect of the HIV/AIDS epidemic that killed much of a generation of African adults and continues to ravage populations. In 2015 alone, 800,000 Africans perished from diseases related to the virus — half the level of a decade earlier.

The other factor is the continued high birth rates in Africa, which create a “youth bulge” of many children per adult, especially as more and more children survive toward adulthood. African women have 4.43 children on average, while the worldwide average is only 2.47. In addition, pronounced and long-term warfare in some countries is also a contributing factor in reducing the adult population and lifting the median age. That is part of why the median age in Somalia is just 16.5 years and 16.8 years in Democratic Republic of the Congo. However, some countries without persistent warfare, such as Burkina Faso have comparably low median ages.

B29.6 is correct: More than half the world population today is younger than 30 years old — 29.6 as of 2015. While Niger has the youngest population worldwide (14.9 years), the oldest worldwide is Japan’s. At 46.3 years, the median age there is more than one and a half times the worldwide number.

The global median age back in 1960 was much younger, at 22.7years, falling as low as 21.5 in 1970, before rebounding toward its current level.

This rise is largely due to longer life expectancies from improving health and survival outcomes in later adulthood, as well as falling fertility rates.

The United Nations estimates that the global median age could rise by 26 percent from today’s level to 37.4 years by 2060 and by 35 percent to 40 years by 2085, reflecting an aging population and declining birth rates.

C37.0 is not correct: China’s median age is 37.0, as of 2015. Its population size will peak in the late 2020s. The continent of Asia’s median age is slightly above the world median, at just 30.3, and 18 percent younger than the median age in China.

China’s median age now is where Europe’s was in the late 1990s. Asia as a whole has a median age today matching Europe’s median age in 1960. The continent’s other billionplus national population, India, has a much younger median age. At 26.7 years, its population is more than 10 years younger than China’s (and nearly 4 years younger than Asia’s overall).

This difference reflects India’s demographic trend relative to China. India’s population size will surpass China’s by about 2022 and continue growing. National median ages in Asia range from one of the world’s youngest (Afghanistan, at 17.3) to the world’s oldest (Japan at 46.3). Several countries in the Middle East with significant youth bulges, such as Yemen also help bring down the median age for Asia below the levels of “graying” countries like China or Japan.

About half of the continent’s population was born around the time of or shortly after many of the globally transformative political events of the 1980s that established the terms of the current era.

D41.6 is not correct: The median age in Europe today is 41.6 years, which means that half of Europe’s population is at least that old. Back in 1955, Europe stood about where the world median is today. Germany, the most populous European Union member, has an even older median age of 45.9. Italy, the major southern European economy, has the same median age as Germany. In 1960, their median ages were 34.7and 31.4, respectively.

The United Kingdom has slightly more favorable population trends than most of the EU, largely due to immigration and children of immigrants, but its median age is already 40.2 as well. France, too, has somewhat favorable demographics, but its median age is 41.2, nearly the same as Europe overall.

Russia, not an EU member, has a younger median age than the continent as a whole, at 38.7 years. In general, Eastern Europe has the youngest median age of any European sub-region. In contrast with Europe, the United States has a similar, but slightly younger median age (37.6) than Russia, approximately matching Europe’s median age in 2000. In contrast, Canada’s — at 40.5 years — is very close to Europe’s number today.