According to General Accountability Office (GAO) Report GAO-04-35, the weekly earnings of full-time working women were about three-fourths of men's during 2001. The report was prepared from a study of the earnings history of over 9,300 Americans for the last 18 years.
Even accounting for factors such as occupation, industry, race, marital status and job tenure, reports the GAO, working women today earn an average of 80 cents for every dollar earned by their male counterparts. This pay gap has persisted for the past two decades, remaining relatively consistent from 1983-2000.
In attempting to explain the discrepancies in pay between men and women, the GAO concluded:
"The world today is vastly different than it was in 1983, but sadly, one thing that has remained the same is the pay gap between men and women," said U.S. Rep. Carolyn Maloney (D-New York, 14th). "After accounting for so many external factors, it seems that still, at the root of it all, men get an inherent annual bonus just for being men. If this continues, the only guarantees in life will be death, taxes and the glass ceiling. We can't let that happen."
This GAO study updates a 2002 report it conducted at the request of Rep. Maloney, which examined the glass ceiling for female and male managers. This year's study used data from a more comprehensive, longitudinal study - the Panel Study of Income Dynamics. The study also accounted for a slew of external factors for the first time, chief among which were the differences in men's and women's work patterns, including more leave from work to care for family.

