By Michael Teich

Millennials need to start putting away money now unless they plan to work until they're 100 years old, said Catherine Collinson, CEO and president of the Transamerica Center for Retirement.

But there's still hope for the generation, she added.

"The great news about millennials is that most millennials are saving, and they're starting at an age that is much younger than any previous generation," Collinson said Tuesday in an interview on Cheddar.

Seven out of 10 millennials are already saving for retirement. The median age of those savers is 24, according to a recent Transamerica retirement survey.

Though the tech-savvy generation is getting off to an early start, 46 percent of millennial workers are concerned they will outlive their savings and investments, the study said. Many are uncertain about Social Security, and 80 percent believe that benefits will disappear before retirement arrives.

"The social securities trustees estimate the trust funds are going to be depleted around 2034, at which time it will only be able to pay about 79 percent of benefits. This is a big deal for millennials, because they don't start turning 65, 66, 67, or retirement age until 10 to 15 years later," Collinson said.

With little confidence in the future of Social Security, millennials are becoming the do-it-yourself retirement generation. More than half expect their main source of retirement income to be self-funded through savings.

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