Death and taxes may be guaranteed, but what happens to an economy when the hereafter becomes a much more distant prospect? Western countries are about to find out. More than half the babies born since 2000 in France, Germany, Italy, Britain, Canada, Japan, and the United States will live past 100, according to a recent study in The Lancet, the British medical journal, charting the astronomical increase in life expectancy experienced since 1840 in developed countries. By midcentury there will be nearly 6 million people over 100 in the world, compared with just 340,000 today, according to the U.S. National Institute on Aging.
The social and economic consequences of a centenarian world are likely to be monumental. One challenge, of course, will be medical costs. Just because people are living longer doesn't mean they're staying healthy as they age, and the price tag just for basic elderly care will be massive. But the more profound change might be in how societies think about work and careers. "The 20th century was a century of redistribution of income," the authors write. "The 21st century could be a century of redistribution of work."
http://www.foreignpolicy.com/articles/2010/04/26/geriatric_world