A survey of millionaires finds that more than half expect to reach 100

French writer and centenarian Jean Anglade poses at his retirement home in Clermont-Ferrand on March 17, 2015 on the eve of his 100th birthday.

The rich are optimistic that they're going to live a long life. Of 5,000 wealthy investors recently surveyed by UBS Wealth Management, each of whom had at least $1 million in investable assets, 53 percent said they were confident they would reach 100. "This is considerably higher than the 80-year life expectancy in most developed countries," reports the Guardian.

"The idea of living a century was once confined to science fiction," states a report titled "The century club." "But no longer. For the world's wealthy, living a 100-year life is not an outcome they consider a mere possibility. It's one they expect."

The high net-worth individuals spanned ten different countries and their outlooks varied based on where they were from. In Germany, for instance, which provides residents with some of the world's best health care, 76 percent of the participants said they expected to become centenarians whereas, in the U.S., only 30 percent were so confident.

UBS Investor Watch: The century club, 2Q 2018

More than 90 percent of the investors said the their wealth enabled them to live a healthier life, the survey found, and nearly the same number of the investors agreed that health is more important than their fortune.

Around half were concerned about rising health care costs and, at 69 percent, Americans were most likely to say that health care is their biggest financial concern. "I don't want to become financially drained and be a burden to my family," said one 66-year-old American.

Many also expressed concern about having less wealth to pass on to their family if they lived that long.

UBS Investor Watch: The century club, 2Q 2018

Overall, 77 percent agreed that working as long as possible is good for your health, though only 52 percent of the wealthy Americans agreed with that sentiment.

Research on that front is mixed. Some studies have shown that retiring early can actually lengthen your life, because work can be stressful and retiring can free you up to exercise and invest more in your health. But work can also help you stay physically active and mentally sharp. Experts recommend that, if you do retire, you find other ways to remain engaged, such as through volunteering.

UBS Investor Watch: The century club, 2Q 2018

Those expecting to make it to 100 seem to be planning accordingly: "Nine in ten investors are taking steps in response to increasing life expectancy, such as adjusting spending habits and financial plans, and allocating their wealth to long-term investments," the report states.

And the investors who expected to make it to 100 were the most likely to make those financial changes. Those from the U.S. and the U.K. were the least likely.

Making it to 100 may be far-fetched

Throughout the world, the average life expectancy at birth in 2015 was 71.4 years, according to the latest data from the World Health Organization. The highest was in Japan at 83.7. For most high-income countries life expectancy teeters around 80 years of age.

Life expectancy does increase as you get older, as an actuarial life table demonstrates, but even when you're in your 90s, reaching 100 isn't necessary likely. American 95-year olds in 2014 had a life expectancy of 98, according to data from the Social Security Administration. In 2011, the U.K.'s Department of Work and Pensions broke down the odds of making it to 100 years of age and found that your chances increase the later you are born but even someone born in 2011, the last year included in the analysis, only has a 29.9 percent chance of making it.

That said, the rich definitely outlive the poor. As research has repeatedly demonstrated, there is "life expectancy gap" based on socioeconomic background. One 2017 study from the Journal of the American Medical Association (JAMA) found that people in rich areas in the U.S. can expect to outlive those in poor areas by at least 20 years.

And that gap is growing. "The rich are enjoying unprecedented longevity," reports Vox, citing another finding about the U.S. from the JAMA in 2016. "From 2001 to 2014, the richest Americans gained about five years of longevity, while life expectancy for the poor didn't budge." The life expectancy of wealthy 50-year-old women jumped more than five years between 1980 and 2010, according to the Washington Post. But for women at that age earning less than average, it actually dropped.

For the millionaires in this survey, of course, only time will tell. But having money increases their chances. As a 28-year-old participant from Switzerland puts it, "If I could use my wealth to live forever, I would."

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