More than half of wealthy investors worldwide expect to live past the age of 100, but Americans are much more pessimistic that they will live that long,  according to a new report.

In “The Century Club,” the first global issue of UBS’ Investor Watch Report, 53 percent of the worldwide respondents in a survey of more than 5,000 millionaire investors expected to live past 100 years old.

U.S. investors were the most pessimistic respondents in the survey. While 49 percent of U.S. high-net worth investors wanted to live to at least 100, only 33 percent believed they would.

Most American respondents felt like they were being realistic about their longevity. Eighty percent of U.S. investors believe the average life expectancy is 80 years old, and many argue that they will not live to 100 due to family history and health care not being advanced enough yet.

Yet three-quarters of the U.S. respondents said they are making financial changes due to increased life expectancy, compared to 90 percent of the global respondents.

Most of the respondents gave at least some credit to their wealth as a driver of their longevity. Globally, 92 percent of the survey participants believed their wealth enabled a healthier lifestyle, compared to 91 percent of U.S. investors. According to UBS, annual health-care costs for investors with more than $10 million are four times those of less wealthy investors.

U.S. investors also prioritize health over wealth, with 77 percent of the U.S. respondents agreeing that health is more important than growing their net worth. Though 76 percent of these respondents were happy with their wealth now, 57 percent were worried that their health would deteriorate over the next decade. The average U.S. respondent would sacrifice 27 percent of their wealth in order to guarantee an extra 10 years of healthy life.

Americans tend to spend the least on gyms, coaches, supplements and other preventative health measures, according to UBS. Americans in the survey were also the most likely to cite health-care cost as their biggest financial concern due to longevity.

Relatively few Americans felt that working as long as possible is good for their health, with only 52 percent agreeing with the idea, compared to an average of 78 percent of worldwide respondents.

UBS surveyed more than 5,000 high-net-worth investors with more than $1 million in investable assets globally, including 1,662 U.S. investors, between December and April.