Mutchler adds, "For 2019, we found that the average income needed by an older individual in rental housing to meet all basic needs was $25,416, and for a couple in rental housing it was $36,204. The index breaks this figure down county by county."

In addition, the index differs from the federal poverty line in that the latter is "way below what an adequate lifestyle requires," Mutchler says in the report. The Elder Index instead "defines economic security as the income level at which older people can cover basic and necessary living expenses without relying on loans, gifts or income support programs like food subsidies and housing assistance. It is also uniquely focused on thresholds specific to older adults' expenses."

It's a big problem, Mutchler says, explaining that "in 2019, half of older Americans living on their own lacked the income needed to pay for their basic needs, as did 23 percent of couples. Taken together, we estimate that more than 10 million people aged 65 or older and living independently have incomes below the Elder Index."

There is, after all, no "family plan" in Medicare, which means that each half of a couple is on the hook for a full individual premium. And other senior expenses aren't necessarily lessened by economies of scale, either, with the people most at risk including women and people of color, who have been running behind, moneywise, all their lives.

The index is intended not just to shape policy regarding such elder supports as Social Security, health care policy, housing needs and retirement savings goals, but also to serve as a guide for financial planning for retirement in a way that will ward off poverty. More discussion is needed by families about how to save and plan for retirement, but that discussion needs to be based on more accurate information about what's actually needed—something the index can help to provide. Currently, the report says, people are not adequately informed about how much they'll need to live on.

Subsidies and benefits for elders need to be expanded, Mutchler points out, since "typically the only people eligible are at or very near poverty levels, rather than being economically insecure." Communities also need to consider affordable senior housing and the necessity of making sure that seniors receive the benefits that are available.

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