The third category, "retirement near the line," refers to the 34% of households whose combined financial assets and Social Security income leave them vulnerable to shocks and unexpected changes such as a major health issue or a significant recession.

The final group is most likely to be secure in most circumstances; this category includes 19% of households. Even among this group, the survey found that one-third of respondents said they were concerned about having enough money for retirement. "These attitudes may lead them to be overly conservative: underspending in retirement or holding too high a percentage of their savings in cash in an inflationary environment," the report said.

One need only look at today's headlines to see why consumers are worried about retirement: increasing economic uncertainty is rising, and it affects people's perceptions about their retirement plans.

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The McKinsey analysis found three main issues in the current environment. One is a wave of early retirements. The Federal Reserve estimated that was an "excess" number of retirements (including 2.4 million baby boomers) during the worst of the COVID-19 pandemic.

In addition, concerns about inflation are high among those nearing retirement. Inflation was the second-most top financial concern by survey respondents, at 20%. It ranked just below medical costs for a serious illness or accident, and ahead of market volatility.

The third concern was around long-term care; the study noted that the National Council on Aging found that about 60% of older adults would not be able to afford more than two years of consecutive long-term care.

The emergence of innovations to address retirement concerns

McKinsey's report outlined a number of strategies and tools for consumers and financial advisors to consider in light of these evolving concerns.

One of the suggestions was personalized financial advice, offered as an employee benefit. "Digitally enabled, low-cost, personalized retirement advice is a requisite for the on-the-line and at-risk segments—and it can be offered to all employees. Our research shows that pre-retirees with an adviser or financial plan are five to 19 times more likely to feel ready for retirement," the report said.

The study also recommends employer-provided retirement advice, offered to non-executive employees. This refers to in-person services, which may be more appealing to baby boomers.

The report also noted that curated annuities could help those at or near retirement age. However, it added that many consumers don't feel they understand annuities, or feel they are too expensive, suggesting more can be done to educate and enable consumers who might consider these products.

"Decumulation robos" was another suggestion from the report. "At-risk and on-the-line households will likely have little to no money to spare in retirement. For them, digital management tools that prompt tax-optimized withdrawals from various retirement accounts, including 401(k), IRA, brokerage, and savings accounts, can create substantial value," the report said.