3. Affluent retirees (19 percent) were more likely to have high levels of financial assets ($320,000 or more) and annual income ($100,000 or more). They were mostly mortgage-free homeowners, with no debt. Affluent retirees reported having access to more diverse sources of retirement income than retirees from the other groups, with defined benefit pension plans and personal savings being the most common.

4. Struggling retirees (18 percent) had low levels of financial assets ($99,000 or less) and income (less than $40,000 annually). They were more likely than any other group to rent rather than own their homes. They also were most likely to have unmanageable debt, such as credit card and medical debt. On average, these retirees rated their health status the worst out of all groups.

5. Just-getting-by retirees (12 percent) also had low levels of financial assets and income, similar to struggling retirees. However, just more than half of them owned their houses free and clear. The majority reported no debt or easily manageable debt.

The study went on to identify several key factors that contribute to retirement status:

• Guaranteed income. Retirees categorized as affluent, comfortable or even average were more likely to have a guaranteed stream from pension plans compared with struggling or just-getting-by retirees The absence of access to lifetime income through a defined benefit plan plays a critical role in retiree outcomes.
• Debt. This appeared to be a key contributor to struggling retirees' lack of satisfaction, anxiety and poor standard of living. Some of these households may have wanted to work longer than they did to pay down debt, but they likely were prevented from doing so because of their health or other issues that out of their control.
• "Correct" amount of spending. Often, this was associated with the desire to maintain the nest egg in case of unexpected needs later in retirement, such as assisted living expenses.
• Retirement tier and advice. Although the survey didn't ask individuals whether they had an advisor, it specifically screened out retirees with more than $1 million in assets. As such, respondents were inherently less likely to have a financial advisor. The traditional role of an advisor is not only one of guiding retirees' investments but also of reinforcing plans and helping them understand whether they're on track. In other words, there is an element of hand-holding that occurs when advisors are available to retirees.

"It is worth pointing out that retirees' paths may be set well before they reach actual retirement age," the study concluded.

"Addressing debt levels well before individuals approach retirement is crucial, as those facing retirement with unmanageable debt may be left with very few options to improve their situation. Further, one must consider not just the financial but the behavioral aspects of retirement and how they factor into spending. Finally, it is critical to recognize that future retirees may face different challenges.

"The best-situated retirees — those who were comfortable or affluent — tended to have more guaranteed sources of retirement income, such as pension plans, than will those retiring after them."

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