World Population Aging: Clocks Illustrate Growth in Population Under Age 5 and Over Age 65
(2011) The world's population is growing—and aging. Very low birth rates in developed countries, coupled with birth rate declines in most developing countries, are projected to increase the population ages 65 and over to the point in 2050 when it will be 2.5 times that of the population ages 0-4. This is an exact reversal of the situation in 1950.