Number aged 100 or over to soar

Rising life expectancy means the number of centenarians in the world will jump 16-fold to 2.2 million by 2050, according to the latest United Nations population report.

About 57 million will be in their 90s and 311 million in their 80s.

Current estimates are that only 66 million people - one in 100 - are 80 or over, and only 135,000 are centenarians.

The world population could be as high as 10.7 billion by 2050, when India, with more than 1.5 billion people, will have overtaken China as the most populous nation, the report says.

It predicts the median age of the world's population will rise from the present 26.1 to 37.8.

The biennial report, which for the first time presents estimates on the numbers of old people, showed that in 13 countries and territories, including Hong Kong, China and Macau, more than 10 per cent of the population would be aged 80 or over by 2050.