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World Population Growth, 1950–2050
For the last 50 years, world population multiplied more rapidly than ever before, and more rapidly than it is projected to grow in the future. In 1950, the world had 2.5 billion people; and in 2005, the world had 6.5 billion people. By 2050, this number could rise to more than 9 billion.
World population expanded to about 300 million by A.D. 1 and continued to grow at a moderate rate. But after the start of the Industrial Revolution in the 18th century, living standards rose and widespread famines and epidemics diminished in some regions. Population growth accelerated. The population climbed to about 760 million in 1750 and reached 1 billion around 1800.
World population growth accelerated after World War II, when the population of less developed countries began to increase dramatically. After millions of years of extremely slow growth, the human population indeed grew explosively, doubling again and again; a billion people were added between 1960 and 1975; another billion were added between 1975 and 1987. Throughout the 20th century each additional billion has been achieved in a shorter period of time. Human population entered the 20th century with 1.6 billion people and left the century with 6.1 billion.
The growth of the last 200 years appears explosive on the historical timeline. The overall effects of this growth on living standards, resource use, and the environment will continue to change the world landscape long after.
The more developed countries in Europe and North America, as well as Japan, Australia, and New Zealand, are growing by less than 1 percent annually. Population growth rates are negative in many European countries, including Russia (-0.5%), Estonia (-0.4%), Hungary (-0.3%), and Ukraine (-0.8%). If the growth rates in these countries continue to fall below zero, population size would slowly decline. As the chart "World Population Growth, 1950–2050" shows, population increase in more developed countries is already low and is expected to stabilize.
Available at: http://www.prb.org/Educators/TeachersGuides/HumanPopulation/PopulationGrowth.aspx
Accessed on May 25, 2010.
Answer the questions.
(A) How big was the World Population after the World War II?
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(B) How big will the World Population be estimated to have in 2050?
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(C) When did the World Population grow faster?
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(D) Why are the growth rates negative in more developed countries?
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