World population growth rate: why declines stalled in the 1980s.

Mortality declines and continuing high birth rates in developing countries combined with the sudden short-term rise in birth rates in the US and other developed countries caused the rate of world population growth to accelerate in the 1950s and 1960s. Following an all-time 2.1% peak rate of global population growth reached in the late 1960s, declining birth rates caused an overall reduction of population growth to 1.7% in the late 1970s. The 1970s was the first period in which the rate of world population growth had ever significantly declined due to family planning. The decline in world births, however, halted in 1980 as the rate of growth stagnated over 1.7% over the 1980s. If the rate of growth remains on this plateau, total population will reach 10.7 billion by 2030. Had growth rate declines of the 1970s continued along the same trajectory in the 1980s, zero population growth could have been reached by 2030 with a total population of 6.7 billion. The stagnation of declining growth is the result of fertility declines which failed to develop or lagged in some developing countries; slow declines in India and China; and the increasing proportion of women at peak childbearing years which raised the birth rate. Ahead, age structure changes will begin to favor a decline in the rate of growth as the proportion of the population who are women of childbearing age begins to decrease. Further fertility decline is expected in China and India. It remains, however, difficult to predict when pre-transition countries will begin to show significant declines.