Higher Population Growth Rates
Global population has skyrocketed since the beginning of the industrial era. from just under 1 billion in 1800 to 1.65 billion in 1900 and to over 6 billion 2000. World population topped 7 by 2012. Rapid population growth began in Europe and other now developed countries. But in recent decades, most population growth has been centered in the developing world. Compared with the developed countries, which often have birth rates near or even below replacement (zero population growth) levels, the low-income developing countries have very high birth rates. More than five-sixths of all the people in the world now live in developing countries; and some 97% of net population growth (births minus deaths) in 2012 took place in developing regions
But population dynamics varies widely among developing countries. Populations of some developing countries, particularly in Africa, continue to grow rapidly.from 1990 to 2008, population in the low-income countries grew at 2.2% per year, compared to 1.3% in the middle-income countries (the high-income countries grew 0.7% per year, reflecting both births and immigration)