For many women in the United States, the gender pay gap is their biggest workplace concern, according to a new survey of more than 9,500 women by the Thomson Reuters Foundation and The Rockefeller Foundation.

The loss of confidence is not misplaced, according to research by the American Association of University Women (AAUW).

Women typically make about 90 percent of men’s earnings until around age 35 but from then to retirement, they make just 75 to 80 percent of what men are paid, the AAUW says.

Census Bureau Data Cited

Overall, women working full-time, year-round, earn 79 cents for every dollar men earn with full-time, year-round jobs, according to the latest Census Bureau data.

Such measurable gaps underscore the issue, says Katherine Gallagher Robbins, Director of Research and Policy Analysis at the National Women’s Law Center in Washington.

“There’s a sense of deep unfairness about it,” Robbins says. “Women are making so much less.”

Concerns Stem from Pay Expectations

Only three in 10 women are confident they earn at least as much as men, the survey found.

Such concern stems in large part from expectations, says Iris Bohnet, director of the Women and Public Policy Program at Harvard University.

“It is not correlated with the size of the pay gap, clearly, but the perception about what is and is not fair,” Bohnet says.

Pay Gap Closing at a Snail’s Pace

The pay gap is closing, but at a snail’s pace. If it continues to move at the same pace it has since 1960, it will take 45 years – until 2059 – for women to earn pay equal to their male colleagues, according to casino games the Institute for Women’s Policy Research.

As years pass, the gap compounds when women get pay increases based on previous salaries, have children or pass up career advances to raise families.

Working for less puts women at a disadvantage in retirement, with smaller nest eggs and lower social security benefits, experts say.