• In low-income countries more than a third of the population is under age 15, while in high-income countries less than a fifth is.
• The world’s population is growing by 200,000 people a day.
• Between 1980 and 2030, the population of low- and middle-income countries will more than double -- to 7.0 billion, compared with 1 billion for high-income countries.
• In the next 35 years, 2.5 billion people will be added to the current population of 6 billion.

Population Growth Rate

Map.

Population growth rate (PGR) is the increase in a country’s population during a period of time, usually one year, expressed as a percentage of the population at the start of that period. It reflects the number of births and deaths during the period and the number of people migrating to and from a country.

Chart 1.

Between 1980 and 2000 total world population grew from 4.4 billion to 6 billion. By 2015, at least another billion people will be added for a total of more than 7 billion. Chart 1 shows that most of this growth has been, and will continue to be, in the developing world. In 1998, 85 percent of the world’s people—more than 4 out of 5—lived in low- and middle-income countries; by 2015, it will be 6 out of 7.

Global trends in population growth rates

Death and birth rates have declined over the past several decades. People are living longer in both industrial and developing countries because of increased access to immunization, primary health care, and disease eradication programs. Many parents are realizing that as health conditions improve, more of their children are likely to survive, so they are choosing to have fewer babies. Increased access to family planning is helping parents control the number and spacing of their children. In addition, with greater access to education and jobs, more women are starting their families later and are having fewer, healthier children.

Chart 2.

Due to the slowing of birth rates, population growth rates have started to decline in the many countries, although they still remain high in some countries because birth rates have not fallen as rapidly as death rates. As Chart 2 shows, population growth rate still tends to be higher in low- and middle-income countries than in high-income countries. Even as the population growth rate has been decreasing in these countries, the number of people added to the population each year has been increasing because the population base has become larger.