Baby boomers are going to live considerably longer on average than members of generations past.
Due in part to improved health measures and better nutrition, mortality rates will drop faster between now and 2022 than they did during the 1915-to-1988 period, calculates Dora Costa, a Massachusetts Institute of Technology economist.
This is part of a worldwide phenomenon Â- a "revolution in longevity."
Since 1950, average life expectancy worldwide has increased 20 years, to 66 years. United Nations demographers expect the average lifespan to reach 76 by 2050. In the United States, people will live even longer than that.
By 2050, the UN says, 21 percent of the planet's population will be over 60. It's currently 10 percent.
This "aging" of the world's population has enormous social and economic consequences for this century. "The shift in policy that is going to be necessary is dramatic," says John Scholvinck, director of social and policy development at the UN in New York.
The aging of the population is no secret among industrial nations, long concerned about the financial security of their social security and medical systems.
What may be less well known is the remarkable demographic transition now under way in many developing countries. As population growth subsides, nutrition and healthcare improve, and youngsters age, they will see their older populations quadruple by 2050.
"It is particularly challenging to developing countries," says Mr. Scholvinck. "They have a much shorter time to adjust."
With high incomes and wealth built up over decades, industrial countries can better afford programs for the aged.
Developing countries are mostly poor. Many have no pension systems, except perhaps for government employees and those working for big firms. Most people rely on children or other family members to take care of them in their old age.
But with increased urbanization Â- people moving from the countryside to seek greater opportunities in cities Â- family structures often break down. "Poverty will be an issue for older people," warns Scholvinck.
Earlier this month in Madrid, the UN held a five-day Second World Assembly on Aging with the theme, a "society for all ages." A few thousand delegates from 142 nations hammered out a 44-page plan of action. Several thousand representatives of nongovernmental organizations (NGOs) held a parallel conference.
The goals set out are idealistic: "Mainstream" aging into global agendas; link aging to social and economic development and human rights; aim some foreign aid at the problems of the aged; recognize the ability of older persons to contribute to society; ensure that older persons age with security and dignity; combat age discrimination.
Specific recommendations number in the dozens. For example, the action plan suggests that labor-market policies enable older persons to continue working as long as they want and are able to do so; that they be given access to technology, continuing education, and on-the-job training; that special efforts be made to provide women and the disabled with jobs.
The UN gathering received relatively little media attention compared with some past major UN sessions. Fighting in the Middle East "took the limelight away," says Scholvinck.
But to UN spokesman Paul Hoeffel, the conference helped boost awareness of the aging issue and pool the knowledge of social scientists, demographers, and other experts.
UN officials are counting on individual governments to act on the suggestions made at the conference, with a political push given by the NGOs. That may be difficult in poorer nations. "There is no infrastructure in many of these countries to even think about these problems," says Mr. Hoeffel.
In general, there was "a tremendous spirit of cooperation" at the UN meeting, he adds. "Everyone had the same feeling, that aging was an issue that all countries have to grapple with seriously."
Meanwhile, every month 1 million people turn 60. And more than 70 million people in the world have marked their 80th birthday. This over-80 group is the fastest growing of all.