Population Projections

Key Facts & Trends

Global population, currently 6.6 billion, is expected to rise to 9.2 billion by 2050. During the past few decades, rising agricultural productivity and declining fertility rates have reduced concerns that population growth rates might lead to global famine, but the challenges posed by increasing numbers of people has not gone away.

 

  • While fertility rates have declined dramatically in Europe and East Asia, fertility and population growth rates remain high in much of Sub-Saharan Africa and South Asia. In sub-Saharan Africa the total fertility rate is 5.5 and in Afghanistan 6.8.
  • Sharp declines in mortality have contributed to global population growth, particularly in less developed countries, where the average life expectancy rose from 41 years in 1950 to 66 years in 2007. 
  • Fertility and population growth rates have declined dramatically in most of the industrialized nations, but America’s population continues to grow rapidly, principally due to immigration.
  • Fertility rates in some European nations have fallen below the level needed to replace current numbers, raising the possibility that  population levels will eventually decline, particularly in Russia, where adult male mortality rates have been on the rise. Nevertheless, birth rates are beginning to rebound in Spain and Italy. 
  • Many developing nations have an unusually high number of young adults (ages 15-29) as a percent of the adult population. A “youth bulge” can produce large increases in population unless potential parents have ready access to family planning services. Between now and 2050 Pakistan’s population is projected to grow from 169 million to 295 million; Afghanistan’s population is expected to surge from 32 million to 82 million. In most of  sub-Saharan Africa, two-thirds or more of the population is under age 30.
  • Although overall world food production remains adequate, population pressures in many parts of the world—particularly in sub-Saharan Africa and South Asia—still result in widespread hunger or malnutrition. Worldwide more than 850 million people are undernourished.  In Afghanistan, Bangladesh, and India more than 40 percent of children under five are underweight. In Chad, 34 percent of all children are underweight.

Policy Implications

World-wide population growth and other demographic trends continue to pose a significant challenge to policymakers.  

 

  • Over the past half decade, global population growth has made a major contribution to the increase in greenhouse gas emissions and will continue to do so in the future.  China, whose population has grown by 50 percent in the past 40 years, will soon be the world’s largest emitter of greenhouse gas emissions.  The United States, currently the largest greenhouse gas emitter in the world, has grown by 100 million people in the past 40 years and will add another 100 million by around 2040.  India, which expects that its greenhouse gas emissions will quintuple by 2050, is projected to grow from 1.1 billion people to nearly 1.8 billion by 2050, overtaking China as the most populous country in the world. 
  • Population pressures are a major contributor to global instability.  “Youth bulges” in areas like the Middle East and in countries like Afghanistan and Pakistan have resulted in large numbers of undereducated and unemployed young people likely to contribute to political unrest.
  • Population growth in many parts of the world is outstripping available water supplies, leading to the depletion of aquifers and the diversion of water from agricultural to residential use.  Water scarcity in many parts of the world could lead to armed conflict as it has in Darfur.
  • Increased population will accelerate the depletion of scarce natural resources and lead to higher commodity prices.  A growing number of experts believe that global oil production—currently 87 million barrels a day—is already at or near its peak. 
  • Global population growth is contributing to deforestation, the loss of important bio-habitats, and the extinction of animal and plant species.  Edward O. Wilson, the Harvard ecologist, estimates that 30 to 50 percent of all species could face extinction by 2050 due to human population pressures.