A new U.N. report on population says within the next 50 years, people over the age of 60 will outnumber children. Drastic improvements in health care for the elderly mean the global population is aging quickly.

Since 1950, life expectancy has risen by 20 years, and stands at a global average of 66.

According to a report compiled by the U.N. Population Division of the Departments of Economic and Social Affairs, men who live to the age 60 can expect to live another 17 years, and women who reach 60 can expect to live another 20.

Improvements in health care and decreased fertility rates are two of the key reasons for this trend.

Population Division Director Joseph Chamie says the effect of this data will be wide-ranging. "The implications are profound, having an impact on economic growth, savings, investments, labor markets, pensions taxations and inter-generational transfers," he said.

One in 10 people worldwide is over 60. Should this trend continue, by the year 2050, that number will drop to one in five. And to project that trend even further, in less than 150 years, one in every three people will be classified as elderly.

The report notes the discrepancy between the developing and developed world. Mortality levels are higher at a younger age in areas of the world classified as developing.

For example, women in the developed world live, on average, to the age of 83; in developing nations the average is 76. Nonetheless, the report notes an increase in the trend across the globe.

In addition, Mr. Chamie notes the effect HIV infection rates have on these statistics, specifically on sub-Saharan African countries where infection rates are the highest in the world. "I have referred to this at times as a 'mortality avalance.' People are ill with HIV, there is no cure in sight, eventually they will die prematurely, because of the HIV. It has enormous impact, of course, on the age structure and on the population," he said.

This report was compiled as part of the preparations for the Second World Assembly on Aging, to be held in Madrid in April.