Around 12.5% of Americans plan to stop working at age 60. Most are also hoping they live to see 100. Financing 40 years of retirement, however, may prove unattainable for many.

Corebridge Financial recently conducted a survey of 2,300 adults to observe how Americans are financially planning for their retirements. Roughly 40% of respondents said their savings will probably fund only up to 20 years. For the 54% who said they want to live to 100, it could mean tough financial times later in life.

Bryan Pinsky, president of individual retirement at Corebridge Financial, told CBS MoneyWatch that “100 is a very long and fulfilling life, and that’s pretty optimistic and great to see. That optimism and hope does come with a little bit of tension — only 27% are very or extremely confident that they won’t outlive their retirement savings.”

Two-thirds of respondents said they fear running out of money more than they fear death. That majority soared to 72% for Gen X respondents, specifically, which were the least confident in their ability to manage retirement savings.

The answer to it all may be an ugly truth — more work.

“If they were to live to 100, 46 percent of those surveyed say they’re extremely or very concerned about the prospect of working an additional 10+ years to fund their retirement,” Corebridge Financial reported.

“And while many are not enthused about the prospect of a longer career, others see the potential for career shifts and want lifelong learning opportunities,” it continued. “Faced with the possibility of longer lives and careers, people may be more likely to embrace working longer if they’re able to continue growing and expanding their knowledge and skills to capitalize on new opportunities.”