Globally, the number of persons aged 60 years or over is expected to almost triple,
increasing from 673 million in 2005 to 2 billion by 2050.
The population of developed countries as a whole is expected to remain virtually unchanged between 2007 and 2050,at about 1.2 billion, according to the medium variant. In contrast, the population of the 50 least developed countries will likely more than double, passing from 0.8 billion in 2007
to 1.7 billion in 2050. Growth in the rest of the developing world is also projected to be
robust, though less rapid, with its population rising from 4.6 billion to 6.2 billion between
2007 and 2050 according to the medium variant.
Another factor contributing to population ageing is the reduction of mortality at adult
ages. Global life expectancy at birth, which is estimated to have risen from 58 years in
1970-1975 to 67 years in 2005-2010, is expected to keep on rising to reach 75 years in
2045-2050. In the more developed regions, the projected increase is from 77 years today
to 82 years by mid-century, and in the less developed regions life expectancy is projected
to rise from 65 years in 2005-2010 to 74 years in 2045-2050.
In terms of annual averages, the major net receivers of international migrants are
projected to be the United States (1.1 million annually), Canada (200,000), Germany
(150,000), Italy (139,000), the United Kingdom (130,000), Spain (123,000) and Australia
(100,000). The countries with the highest levels of net emigration are projected to be:
China (-329,000 annually) Mexico (-306,000), India (-241,000), Philippines (-180,000),
Pakistan (-167,000) and Indonesia (-164,000).
