Decades after women entered the labor force en masse, pay disparity between genders has fallen but not disappeared, according to a report from the Labor Department.
For the first quarter of this year women had median usual weekly earnings of $665, or almost 79 percent of the $844 that men earned, according to the study. In the first quarter of 2000, women earned about 76 percent of men's income.
"Not only has the education gap between men and women narrowed, but labor market experience has narrowed because women have been working more and more, and more consistently," said Harry Holzer, an economist at Georgetown University and the Urban Institute.
However, the remaining gap is still cause for concern, he said.
"Big progress has been made, but a 20 percent pay gap remains significant," Holzer said.
Further, he added, part of the narrowing could be due to men taking a greater beating in the recession than women. During the recession, men lost more jobs than women, and as of March the seasonally adjusted unemployment rate among adult men 20 and older was 10 percent compared with 8 percent for adult women.
In a study of the federal work force published last year, congressional investigators found that the difference between men's and women's average annual salary declined from 28 cents to 11 cents on the dollar from 1988 to 2007. While the Government Accountability Office found that the pay gap declined primarily because men and women have become more similar when it comes to experience, educational attainment and other characteristics, an unaccounted-for gap remained.
Why does a gap among the broader work force remain? Some say women accumulate less experience due to family care giving, crimping lifetime earnings. Others, such as Kim Gandy, past president of the National Organization for Women, attribute the persistent pay gap to sexism.
"It's a travesty that in this day and age women are making less than 80 cents on a dollar compared to men," Gandy said. "There have been a lot of efforts to explain it away. After controlling for all variables, there is still a significant wage gap that can only be explained by discrimination."
According to the Institute for Women's Policy Research, occupations dominated by males pay more than those dominated by females at similar skill levels.
"Therefore, tackling occupational segregation is an important part of tackling the gender wage gap," according to organization.
Whatever the cause of the gap, pay inequity is "not just an issue for women," President Barack Obama said last month.
"American families, communities, and our entire economy suffer as a result of this disparity," Obama said.
Indeed, women constitute half of the nation's nonfarm employees, and are a major force within the economy and their families. The recession has increased their relative importance as men have been laid off, according to the liberal Center for American Progress.
"This loss of a man's paycheck means that millions of families now rely on a woman's job to make ends meet," according to a statement from the center. "The persistent gender pay gap is adding insult to injury for families already hit hard by unemployment."
The Obama administration has taken some steps to end pay discrimination. Last year, the president signed into law the Lilly Ledbetter Fair Pay Act, which makes it easier to file charges against employers for discrimination in paychecks. Congress has also been working on legislation that would add muscle to existing equal-pay laws.