Executive Summary

All populations, like all individuals, must address issues of age. Unlike people, however, populations can stay young indefinitely and can even grow younger with time. This report is about the ages of populations, how age is structured within populations, why that matters, and how governments and societies can influence population age structure. Age structures, or population profiles when they are pictured graphically as in this report, demonstrate the comparative sizes of specific age groups relative to others or to the population as a whole. These age structures yield insights into many of the political, economic and security challenges that countries face, now and in the future. Age structures carry particular importance when a large proportion of a country's population is passing through one of life's dependent stages, such as childhood or old age, or when a small proportion is passing through an age of productivity. In these cases, society's resources are likely to be stretched and a government's stability and political and economic management are likely to be tested.

The Shape of Things to Come presents evidence that certain age structures in populations can support governments' efforts to create and maintain political stability, and that others can impede such efforts. The report does not argue that these demographic structures and their dynamics directly cause development failures or successes. Yet the influence of age structure on a state's progress toward democracy, on the risk of an outbreak of civil conflict and on economic development is both significant and quantifiable.

This report identifies for the first time four main types of age structures present in current populations: very young, youthful, transitional and mature. Chapters for each structure type describe their basic demographic parameters and the common development challenges and opportunities faced. A quantitative analysis shows that each structure has distinct traits in vulnerability to civil conflict, governance and economic growth.

Each chapter also profiles one or two countries representative of the age structure type. The case study analysis aims to represent as many major regions of the world as possible, and individual countries were selected for their interest to international policymakers and/or because their demographic history has been particularly noteworthy. Some of the countries profiled, such as Germany, Mexico and Nigeria, face demographic scenarios that are emblematic of others in their age structure category or geographic region. The governments of other countries profiled, such as Iran and Tunisia, have made uncommon policy decisions that uniquely affected their demographic progress. This group of both archetypical and distinctive case studies should offer a wide range of possibilities and lessons applicable to other countries. Specific recommendations for the following key findings are offered following this summary.

Graphic representations of age structures, such as this one, are used throughout this publication. They demonstrate the proportional size of different age groups within a population at a given point in time by showing the percent of a country's total population that is comprised of males and females within five-year age groups. Along the side of the graph, the current age of members of each group, based on the year from which the profile is drawn, and their birth years are shown. Ethiopia is an example of a country with a very young age structure, which will be explained further in Chapter Two.

 

Graphic representations of age structures, such as this one, are used throughout this publication. They demonstrate the proportional size of different age groups within a population at a given point in time by showing the percent of a country's total population that is comprised of males and females within five-year age groups. Along the side of the graph, the current age of members of each group, based on the year from which the profile is drawn, and their birth years are shown. Ethiopia is an example of a country with a very young age structure, which will be explained further in Chapter Two.

Key Findings

Population age structure has significant impacts on countries' stability, governance, economic development and social well-being.

Very young and youthful age structures are most likely to undermine countries' development and security. Between 1970 and 1999, 80 percent of all civil conflicts that caused at least 25 deaths occurred in countries in which 60 percent or more of the population was under age 30. During the 1990s, countries with a very young structure were three times more likely to experience civil conflict than countries with a mature age structure. Nearly 90 percent of countries with very young structures had autocratic or weakly democratic governments at the end of the 20th century.

Countries in the transitional category stand to experience significant benefits from demographic change, if their governments take advantage of the opportunity it presents. Between 1970 and 1999, these countries experienced an average annual economic growth rate of 3.6 percent, which may be due to their reduced dependency ratios that allow greater personal savings and government spending. Their vulnerability to civil conflict and likelihood of undemocratic governance also decreased dramatically.

Countries with a mature age structure, in which more than 55 percent of the population is above age 30, have generally been the most stable, democratic and highly developed. In the 1980s, none of these countries experienced civil conflict, and in the 1990s, only two did. More than 80 percent of countries with mature structures over the time period analyzed have been full democracies. Countries with a mature population have low rates of economic growth. But because they typically also have very high national incomes, so far this slower expansion has not had major repercussions.

Societies, and especially governments, can influence age structures through policies that affect the demographic forces—births, deaths and migration— that shape these structures. Demographic-based policies that have worked successfully in many countries with transitional and mature age structures include improving access to family planning and reproductive health care, education for girls and economic opportunities for women.