World population reaches turning point

Posted: 3 January 2011

World population has reached a transition point: the rapid growth of the second half of the 20th century has slowed, but numbers will reach 7 billion in 2011.

Indeed, factors such as continuously improving mortality and slower-than-expected declines in birth rates guarantee continued growth for decades, says a commentary accompanying the 2010 World Populaton Data Sheet from the Population Refence Bureau.

The questions remain: how fast, how much, and where? The PRB chart shows that the population size of the world's more developed countries has essentially peaked. What little growth remains will mostly come from immigration from less developed countries. A number of more developed countries are likely to decline in size and see the proportion of their elderly populations rise to unprecedented levels.

One example of this is Japan where population fell by 123,000 last year - the biggest drop since records began in 1947, according ro a startement this week by the Ministry of Welfare. It is the fourth consecutive year in which the population has declined. While births were similar to the previous year, deaths soared by an estimated 52,000 to a record of 1,194,000, as against an estimated 1,071,000 births.

Fertility rates

The outlook for less developed countries is quite different. The increase in world population from 1.6 billion in 1900 to 6.1 billion in 2000 was almost entirely due to population growth in those countries. The 20th-century population "explosion" was a direct result of the rapid decline in mortality rates in less developed countries.

"There are two major trends in world population today," says Bill Butz, PRB's president. "On the one hand, chronically low birth rates in developed countries are beginning to challenge the health and financial security of their elderly. On the other, the developing countries are adding over 80 million to the population every year and the poorest of those countries are adding 20 million, exacerbating poverty and threatening the environment."

Global population rose to 6.9 billion in 2010, with nearly all of that growth in the world’s developing countries. In contrast, the world's developed countries, totaling 1.2 billion people, saw their populations continue to age as the numbers of those of working age dwindle. For example, Japan has a total fertility rate of 1.4 children per woman, and an elderly support ratio of 3 — the lowest in the world, along with Germany and Italy. By 2050, Japan will have only 1 working-age adult for every elderly person; Germany and Italy will each have 2. "In 2011, world population will reach 7 billion, just 12 years after reaching 6 billion,” says Carl Haub, PRB's senior demographer and author of this year's data sheet. "It also took 12 years to climb from 5 billion to 6 billion. The big question now is when will we reach 8 billion? Most likely in 2024, 13 years after the seventh billion, but it could be sooner."

The 2010 World Population Data Sheet shows the contrasts between developing and developed countries. Comparing Ethiopia and Germany illustrates how stark the contrasts can be. Even though Ethiopia and Germany have almost the same population size today, Ethiopia is projected to more than double its population from 85 million today to 174 million in 2050. Germany’s population will likely decline from 82 million to 72 million over that same time. The cause of these enormous differences is lifetime births per woman. Ethiopia's total fertility rate of 5.4 is four times greater than Germany's rate of 1.3.

Other highlights

  • The worldwide recession appears to have caused declines in birth rates in some developed countries, such as Spain and the United States; and slowed down increases where birth rates had begun to rise, such as in Norway and Russia.
  • Africa's population is projected to double to 2 billion by 2050, although this growth could be greater if birth rates do not decrease faster than currently. Africa's total fertility rate is 4.7 children per woman.
  • Worldwide, 40 per cent of the population, or more than 2.7 billion people, lack access to an adequate sanitation facility. The bulk of the underserved live in rural areas of developing countries. Only 40 per cent of people in rural areas in these countries access to any sanitary facilities.