♤ Globally, population aged 60 or over is the fastest growing:

As fertility declines and life expectancy rises, the proportion of the population above a certain age rises. This phenomenon, known as population ageing, is occurring throughout the world. By 2050, all major areas of the world except Africa will have nearly a quarter or more of their populations aged 60 or over.

Population ageing is projected to have a profound effect on the number of workers per retiree in various countries, as measured by the Potential Support Ratio (PSR), defined as the number of people aged 20 to 64 divided by the number of people aged 65 and over. Currently, African countries, on average, have 12.9 people aged 20 to 64 for every person aged 65 or above, while Asian countries have PSRs of 8.0, Europe and Northern America at or under 4. Japan, at 2.1, has the lowest PSR in the world (although seven European countries also have PSRs below 3). This will put fiscal and political pressures on the health care systems as well as the old-age and social protection systems of many countries in the not-too-distant future.