Look who's retiring later

Mature businessman looking at watch
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Getting ready to retire? Hold that thought.

Two-thirds of Americans have experienced a financial disruption that affected their financial behavior in some way, according to a newly released data by TD Ameritrade. And of that group, roughly half expect to delay or forgo retirement as a result of the disruption. The 34 percent who plan to put off retiring are moving their target age from 63, on average, to 68.

Further underscoring many Americans' lack of a savings cushion, just one-fifth of those who experienced a financial disruption believe they have recovered financially.

"The fact that there are financial disruptions was not surprising. We have seen evidence that financial disruption happens throughout life," said Matt Sadowsky, TD Ameritrade's director of retirement and annuities. But the length of time people need to recover, he said, "is pretty eye opening."

Savings under scrutiny

Retire well: Salary saving tips
Retire well: Salary saving tips   

The findings are being released at a time when Americans' term savings are under scrutiny.

Average retirement account balances have grown rapidly in recent years, thanks in part to a strong stock market. And the number of Americans with 401(k) accounts has risen.

Read MoreSurge in 401(k) millionaires as balances hit new highs

That shift "shows that the 401(k) plan can indeed build a significant nest egg," said Sarah Holden, senior director of retirement and investor research at the Investment Company Institute (ICI). The institute has collaborated with the Employee Benefit Research Institute to analyze how much an individual with 401(k) accounts available throughout his or her career would actually save. The conclusion, Holden said, was that even when people are less than perfect savers, a 401(k) can indeed provide significant income in retirement.

But the growth in 401(k) balances has only helped those who have retirement savings, and almost 40 million working age households do not, according to the National Institute for Retirement Security. (That institute found that about half of the households without retirement savings are headed by someone aged 45 to 65, though the ICI, in its own study, found that roughly eight out of 10 households nearing retirement have some retirement assets.)

Sadowsky pointed out that a third of retired Americans get 90 percent or more of their income from Social Security.

"Throughout our history, we just have not done a good job of saving," he said. "If you don't have an emergency fund and a plan in place with multiple scenarios planned out, there is certainly going to be fear that you are not going to be able to respond in a timely manner" to a financial disruption.

Read MoreTime to call it: The 401(k) is a failure

Encouraging savings

A growing number of employers are taking steps to encourage Americans to save. The number of employers automatically enrolling employees in retirement plans has increased 70 percent since the end of 2008, according to research by the Vanguard Group. That feature significantly boosts participation: a WorldatWork survey found that 37 percent of plans with automatic enrollment had 80 to 89 percent of employees participating, compared with 21 percent of plans that did not have that feature.

For now, though, Americans' financial vulnerability remains. "From a broader landscape, there is not as much savings as there could be," said Sadowsky.