ABSTRACT
The populations of most developed countries are projected to go through significant ageing during the first half of this century. In the past 25 years the number of people aged 65 and over in OECD countries rose by forty-five million, whereas the working-age population increased by 120 million. However, in the next 25 years, the number of non-working elderly will increase by seventy million while the working population will rise by only five million. 1 Figure 17.1 shows the projected changes in the old-age dependency ratio between 1990 and 2150. This figure indicates that developed countries will experience dramatic population ageing until 2050, after which the dependency ratio levels off.
