While the poor retirement preparedness of U.S. workers in general is common knowledge, there are special challenges facing women, minorities and millennials.

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That’s according to a white paper from the Washington, D.C.-based Financial Services Roundtable, which pointed out that while “[w]omen comprise 47 percent of the labor force in America, and women over 25 are nearly as likely to have earned a bachelor’s degree as men — 29.6 percent of women compared to 30.4 percent of men” — that’s not an indication of parity in pay, with women’s median weekly earnings for full-time wages and salaries only amount to approximately 81 percent of what men make.

In fact, with 27 percent of women working only part time, and many leaving the workplace to raise children or care for other family members, their opportunities for earning and advancement are limited.

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This has an effect on their retirement savings as well, despite the fact that they actually need more money than men to prepare for a longer average lifespan — 87 years, compared with 84 — and the greater likelihood that they will need to spend more over that time for health care.

But women aren’t saving enough, the paper said. Part-time workers aren’t usually eligible for retirement plans, and pension benefits are usually lower for women based on lower earnings.

In addition, women don’t save at a high enough rate to cover retirement expenses: while 62 percent of women are offered a 401(k) or similar retirement plan, the paper said, and 76 percent participate, they only save at a rate of 7 percent of their salary.

Minorities face challenges as well. The paper cited Economic Policy Institute figures indicating that only 26 percent of Hispanic families had savings in a retirement plan or IRA, compared to 41 percent of black families, 65 percent of white families and 58 percent of Asian families.

And among minority households with retirement savings, 75 percent have less than $10,000 and the median balance for retirement account assets is $30,000 for near retirees.

Bureau of Labor Statistics figures indicate that 65 percent of employed Hispanic women and 59 percent of employed black women work in low-wage jobs including service, sales, and office occupations, and employed black and Hispanic men are also more likely to work in low-wage jobs including construction, production, maintenance, and transportation. While that means they’re also less likely to have access to retirement plans, those aren’t the only challenges they face.

An Ariel/Hewitt study indicated that African-Americans and Hispanics are more likely to borrow from retirement accounts, and also stick with safer investments that offer less opportunity for growth. Both of these can also result in lower retirement savings balances.

Millennials, for their part, have set debt repayment as their top priority. With student loan debt “crowding out other investments,” the paper said that an average student debt of $53,000 “leads to a lifetime wealth loss of nearly $208,000” between reduced retirement savings and lower home equity.