0.2 Historic perspectives: economic and population growth  (Page 7/10)

Then world population doubled again from 1850-1950 (100 years) and doubled again in the next 50 years.

Notice in Table 4 that the interval for doubling of population fell from 1300 years to only 50 years by the year 2000.

This record was the basis for some very gloomy predictions about population in the last part of the 20th Century, as we shall see.

Population today

What is the total population of low and middle income nations?
2 billion? 4 billion?
Answer: 5.6 billion

What was the average annual population growth for the world from 1990-2007?
1.0%? 1.3%? 1.8%? 2.0%?
Answer: 1.3%

And for low and middle income nations?
1.5%? 2.0%? 2.5%?
Answer: 1.5%

In the 1960s and the 1970s and part of the 1980s, economists, demographers, U.N. agencies, etc. “reasoned” that the “ever-contracting” period of population doubling was inevitable .

In the seventies and eighties demographic experts at Stanford and in the U.N. were predicting a runaway growth in world population, with most of the growth coming in developing countries.

A review of the eighties literature on economic development and population is revealing. No phrase was more politically correct in the seventies and eighties and even in early nineties then the dreaded words “world population explosion .”

But a strange thing happened on the way to the explosion. This has become one of the central lessons of development economics today.

The world is now in midst of sharp demographic transition : widespread decline in birthrates and death rates. We can represent the demographic transition as in Figure 3 .

Another most welcome feature of the demographic transition since 1970 has been very sharp gains in the life expectancy in emerging nations.

But even more striking was what happened to fertility. As late as the 1980s seers such as Paul Erlich of Stanford were issuing shrill warnings about the effects of high birthrates. Erlich wrote a book called The Population Bomb Published by the Sierra Club/Ballantine Books in 1968. . But in the past three decades, population growth has been leveling all over most of the world, often sharply. About one-third of countries now have birthrates below the 2.1 children per woman that is the population replacement level. The "population explosion" has " imploded ."

Instead, there is now a "birth-death" in many nations, including Japan, South Korea, Italy, Spain, Germany and Russia (fertility below 2.1). China, should it continue its one child per family policy much longer, will soon follow that pattern.

But even more striking, fertility rates Strictly speaking, the measure of fertility is the total fertility rate (TFR). The TFR is the number of children an average woman would have in her lifetime if age-specific fertility rates remained constant. (number of children born to each female of child-bearing age) are declining all over the world , including virtually all developing nations outside of a few in Africa and the Middle East.