Related: Democratic party shifting left on Social Security

One in four women age 65 or older receive 90% of their income from Social Security, compared with less than one in five men. Unmarried retirees are twice as likely as married retirees to rely on Social Security for more than 90% of their income.

“Without Social Security income, the poverty rate among women 65 and older would increase from 12% to over 45%,” the report notes, citing a 2015 report from the Center on Budget and Policy Priorities. The comparable numbers for black and Hispanic seniors without Social Security payments is also around 50%, according to JEC calculations based on Census Bureau data.

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“Social Security has been a pillar of economic and retirement security for more than 80 years,” said Rep. Carolyn Maloney (D-N.Y.), ranking member of the committee, in a press release. “It will be even more important in the coming decades.”

One reasons for that: the decline of pensions. Roughly 80% of employees at medium or large firms had pensions in 1985, comapred with less than 30% today, according to the report, citing the Employee Benefit Research Institute and the Bureau of Labor Statistics.

Many employees have the option of saving for retirement through defined contribution plans, which often include some matching funds from employers, but aren’t able to save much.

“Slow wage growth and rising costs of living have made it hard for many families to save for retirement,” according to the report, noting that average weekly earnings of production and nonsupervisory workers, adjusted for inflation, are lower today than they were in the 1970s while spending for education, health care and child care have grown.

Those workers and others will need Social Security to fund their retirement, and there will be less money in the future. Unless measures are taken to shore up the program, Social Security payments will be reduced by about 25% after 2034, according to the latest Social Security Trustees report.

The Joint Economic Committee Democratic report doesn’t offer much in the way of shoring up Social Security except to say that raising the maximum level of income subject to the Social Security payroll tax “would increase the progressivity of Social Security, since a greater share of high earners’ wages would be subject to tax and the higher benefits they would receive [because they live longer than other wage earners] would not equal the higher taxes paid into the program.”

Alicia Munnell, director of the Center for Retirement Research at Boston College, has written that “the long-run deficit” of Social Security “can be eliminated only by putting more money into the system or by cutting benefits. There is no silver bullet. … [and] “stabilizing the system’s finances should be a high priority to restore confidence in our ability to manage our fiscal policy and to assure working Americans that they will receive the income they need in retirement.”

Laurence Kotlikoff, an economics professor at Boston University and the author of several books on Social Security, says the shortfall in Social Security funds is many times larger than Social Security Trustees report finds — close to $32 trillion if the present future value of financing Social Security is applied against the present future value of liabilities.

Kotlikoff, who is running for president as a write-in candidate, suggests instead a complete overhaul of the Social Security program along with a totally new tax system heavily focused on consumption instead of income. Social Security would be replaced by a personal savings program in which everyone would have to contribute 10% of their income. More about the plan can be found at Kotlikoff for 2016.