Demographic Development – Reversing Course?

By Elizabeth Leahy

With the largest population in Africa, Nigeria’s political and economic developments reverberate across the continent. Nigeria chairs the Economic Community of West African States (ECOWAS) and is the eighth largest oil exporting country in the world. More than 40 percent of the region’s gross domestic product is accounted for by Nigeria’s economy, and the petroleum industry is responsible for about two-thirds of national revenue and a great deal of international interest in the country. Yet the government maintains a delicate hold on democracy, and the country has recently experienced political instability. Throughout 2006, militant rebels angry about the distribution of oil revenue have conducted a series of attacks against the industry, including kidnapping foreign workers, which resulted in the country’s petroleum output dropping by 25 percent.1 Most of these angry rebels are young men.

The lens of population age structure—that is, the proportional size of different age groups within a population—is useful for better understanding Nigeria’s development and that of many other countries. Age structures reflect a country’s present and past mortality and fertility trends, which can be extrapolated to broader health and development dynamics. Age structures also yield insights into national political and economic challenges, now and in the future.

Population Action International (PAI) has developed four major types into which all current and past national populations fit: very youthful, youthful, mid-age and aged age structures. As PAI’s forthcoming report The Shape of Things to Come: Population Age Structures and their Implications for Security, Governance and Economic Development explains, countries in each age structure category share similarities in important development indicators: their governance type, economic development, and vulnerability to civil conflict. Although population dynamics provide only a partial view of a country’s current and future risks and opportunities, the associations found in comparing age structures suggest that demographics should be a component of all country analyses. A case study such as Nigeria’s can help policymakers see how the relationship between population and development has evolved in a specific case, and how its findings might be carried over to other countries.

Nigeria is firmly within the category of a very youthful age structure, with nearly three-quarters of its population under the age of 30. Among the 62 countries in the very youthful category in 2005, at least two-thirds of the population was generally under age 30 and just three to six percent was older than age 60. These countries are in the early stages of the demographic transition: the shift from large families and short lives to small families and longer lifespans. However, in some cases, countries’ initial success in reducing birth and death rates has not been sustained over time. Nigeria’s population has actually grown more unbalanced in recent decades. Between 1975 and 2005 the share of young people in the country’s population increased while the share of older adults slightly decreased, and thus Nigeria has reversed course along the path of the demographic transition—an anomaly in the process of most countries’ development.


These two population profiles compare the size of different age groups in Nigeria’s population in 1975 and in 2005. The bars along the left side represent males, the right side, females; each bar shows the relative size of a five-year age cohort in ascending age. In both of the years shown, Nigeria’s population maintains the classic pyramid shape of a very youthful population, with progressively larger proportions among each successively younger age group.

Nigeria’s regression along the demographic transition can be explained by its stagnant death rate and only slightly declining birth rate. Mortality rates have barely changed since 1975, from 20 to 19 annual deaths per 1,000 people. Total life expectancy is around 44 years for men and women, a decline from previous decades. Meanwhile, the total fertility rate dropped from 6.9 to 5.9 children per woman between 1975 and 2005, but remains extremely high. As fertility and mortality rates have remained high, the momentum of population growth has led the share of children and adolescents within the population to increase, making Nigeria’s age structure even more unbalanced.

Only eight percent of married women of reproductive age use a modern method of contraception. This may in part be because desired fertility is very high—the number of children Nigerian women say they want is nearly seven. A number of factors may explain high desired fertility, including poor child survival rates and low educational attainment among women. One-fifth of all children born in Nigeria die before they turn five, and 42 percent of women have never attended school.3

Governments in countries with very youthful age structures tend to face increased pressures for natural and economic resources and social services, as continually larger shares of the population pass through the dependent ages in childhood and adolescence. Countries with very youthful age structures are significantly less likely to be stable democracies than those with more balanced populations. Following the end of military rule in 1999, Nigeria was rated a partial democracy, an improvement from 15 years spent under an autocratic regime.4 Still, the country has particularly struggled with issues of corruption: state governors are immune from prosecution within the country’s borders and the vice president has been implicated as accepting bribes from a U.S. Congressman.5 Despite President Olusegun Obasanjo’s promises of reforms, no high-ranking government official has yet been convicted of corruption during his presidency. Earlier this year, an unsuccessful attempt, probably supported by Obasanjo, was made to alter the country’s constitution to allow him to run for a third term in office. Elections in 2007 will mark the first time that one democratically elected Nigerian president turns over power to another. 6Although many previous international development projects yielded poor results, Nigeria and its donors have taken steps to reduce its debt to foreign creditors. Through currently active projects, the World Bank is funding nearly $2 billion in development assistance to the country. Still, one-third of the population lives in poverty, and Nigeria is among the 20 poorest countries in the world.

Table 1. Current Demographic Statistics for Nigeria7

Population 1975 59.0 million
Population 2005 131.5 million
Population 2025 (medium term projection) 190.3 million
Population 2050 (medium term projection) 258.1 million
Contraceptive prevalence rate 8.2%
Total fertility rate (2005-2010) 5.32
Unmet need for family planning, married
women of reproductive age
Median population ages 17.5 year
Population under age 15 44.3%
Life expectancy 44.1 years men
44.3 years women
Adult literacy rate (2003) 66.8% total
59.4% women
Population living below poverty line 34.1%
Unemployment rate 2.9%
Primary occupations (1999) agriculture 70%
services 20%
industry 10%
Major religions Muslim 50%
Christian 40%
indigenous 10%
HIV prevalence rate (ages 15-49, 2005) 3.9
Arable land (% of total) 33.0
GNI per capita (Atlas method, current US$, 2005) $560

Nigeria’s population more than doubled between 1975 and 2005, and it is projected to increase by 40 percent by 2025. As measured by population size, the country is currently the ninth largest in the world. Even if its fertility and mortality rates begin a rapid decline, Nigeria will have a youthful age structure in 2025. Now that the country has established a democratic government and increased support from international donors, priority must be given to improving its people’s standard of living. Age structures can and have been influenced by populationrelevant policies and programs. In particular, expanding access to family planning and reproductive health care, education for girls, and economic opportunities for women can enhance development and improve the prospects for global security. Improvements in health and economics would likely lead to a much more stable situation for one of Africa’s leading states. Critical areas include maternal and child health, greater access to basic education, increased use of contraception, entrenchment against HIV/AIDS and other infectious diseases, and a more equitable distribution of wealth, together with other programs to diversify and balance the economy.

As shown in Figure 2, there are a range of demographic possibilities for Nigeria within the next 20 years. The United Nations produces future population projections at two extremes, a low- and high-fertility variant, each of which assumes vastly different future birth rates. As can be seen in the profile, if fertility declines rapidly in Nigeria to about three children per woman, the proportion of its population composed of age groups under 30 will begin to even out and produce a more stable age structure. This could occur if priority attention is given to both mortality and fertility aspects of health by the country’s government and its partners. However, if total fertility declines from today’s rate of more than five children per woman to four, Nigeria will maintain its current unbalanced very youthful age structure, which would likely prolong and exacerbate its development challenges.


As reflected in the UN’s high fertility projection, even a modest decline in Nigeria’s current fertility rate will not dramatically change its age profile within the short term. However, the UN’s most optimistic scenario, which reflects a decline in fertility rates to three children per woman, would in fact place the country on a path towards greater age balance.

Elizabeth Leahy is a research assistant at PAI and co-author, with Richard Cincotta, of the forthcoming report, The Shape of Things to Come: Population Age Structures and their Implications for Security, Governance and Economic Development, from which the material for this research commentary was drawn. The Shape of Things to Come will be published by PAI in 2007.


  • Mahtani, D. 2006. “Nigeria’s Oil Delta Crackdown Heightens Fear of Attacks.”Financial Times, 22 August, 6.
  • United Nations Population Division. 2005. World Population Prospects: The 2004Revision. New York: UN Population Division.
  • National Population Commission [Nigeria] and ORC/ MACRO. 2004. Nigeria Demographic and Health Survey 2003. Calverton, Maryland: National Population Commission and ORC/MACRO.
  • University of Maryland Center for International Development and Conflict Management. 2005. “Polity IV Project: Political Regime Characteristics and Transitions, 1800-2003.” Available online here ; last accessed 17 August 2006.
  • Shenon, P. 2006. “Nigerian Official Denies Congressman Bribed Him.” The New York Times, 20 July, A19; 2005. “The Fat of the Land.” The Economist, 25 October.
  • 2006. “A President Frustrated.” The Economist, 20 May.
  • UN Population Division. 2005. World Population Prospects: The 2004 Revision. New York: UN Population Division; World Bank. 2004. World Development Report 2005. Washington, DC: World Bank; United Nations Educational, Scientific and Cultural Organization (UNESCO); Central Intelligence Agency (CIA). The World Factbook 2006.