In 2010, an estimated 524 million people were aged 65 or older 8 percent of the world’s population. By 2050, this number is expected to nearly triple to about 1.5 billion, representing 16 percent of the world’s population. Although more developed countries have the oldest population profiles, the vast majority of older people and the most rapidly aging populations are in less developed countries. Between 2010 and 2050, the number of older people in less developed countries is projected to increase more than 250 percent, compared with a 71 percent increase in developed countries.
Most developed nations have had decades to adjust to their changing age structures. It took more than 100 years for the share of France’s population aged 65 or older to rise from 7 percent to 14 percent. In contrast, many less developed countries are experiencing a rapid increase in the number and percentage of older people, often within a single generation (Figure 2). For example, the same demographic aging that unfolded over more than a century in France will occur in just two decades in Brazil. Developing countries will need to adapt quickly to this new reality.