Summary

Although the pay gap between men and women in the U.S. workforce has narrowed since the 1980s, numerous studies have found that a disparity still exists. In 2003, we found that women in the general workforce earned, on average, 20 cents less for every dollar earned by men in 2000 when differences in work patterns, industry, occupation, marital status, and other factors were taken into account. Other research indicates that this disparity existed for federal workers as well. For example, a 1998 study showed that the pay gap between men and women in the federal workforce decreased significantly between 1976 and 1995, but in 1995 white women still earned 14 cents less for every dollar earned by white men and African-American women earned 8 cents less for every dollar earned by African-American men after available factors related to pay were taken into account. In light of concerns that a pay gap may continue to exist between men and women in the workplace, Congress asked us to examine pay disparity issues and the role the federal government has played in enforcing anti-discrimination laws. In agreement with Congressional staff, we addressed these questions in two separate, consecutive reports, the first of which focused on enforcement and outreach efforts in the private sector and among federal contractors. This second report addresses the following question: To what extent has the pay gap between men and women in the federal workforce changed over the past 20 years and what factors account for the gap? To answer this question, we used two approaches to analyze data from the Central Personnel Data File (CPDF)--maintained by the Office of Personnel Management (OPM)--covering a 20-year period. First, we looked at "snapshots" of the federal workforce at three points in time (1988, 1998, and 2007) to show changes in the federal workforce over a 20-year period. Second, we examined the cohort (or group) of employees who joined the federal workforce in 1988 and tracked their careers over the course of 20 years to look for differences in the pay gap in this group. We used CPDF data to generate summary statistics on the federal workforce and to perform multivariate analyses, which we used to identify the amount of the gender pay gap attributable to differences in measurable factors--such as work-related and demographic characteristics of men and women. To further inform our analyses, we reviewed existing literature and reports on gender and pay and interviewed officials at the Office of Personnel Management and the Equal Employment Opportunity Commission (EEOC).

From 1988 to 2007, the gender pay gap--the difference between men's and women's average annual salary in the federal workforce--declined from 28 cents to 11 cents on the dollar. For each year we examined, all but about 7 cents of the gap can be accounted for by differences in measurable factors such as the occupations of men and women and, to a lesser extent, other factors such as years of federal experience and level of education. The pay gap narrowed as men and women in the federal workforce increasingly shared similar characteristics in terms of the jobs they held, their levels of experience, and educational attainment. Factors for which we lacked data or are difficult to measure, such as work experience outside the federal government and discrimination, may account for some or all of the remaining 7 cent gap. (2) Our case study analysis of workers who entered the federal workforce in 1988 showed that their pay gap grew from 22 cents in 1988 to a maximum of 28 cents in 1993 through 1996 and then declined to 25 cents in 2007. As with the federal workforce, differences between men and women that can affect pay, especially occupation, accounted for a significant portion of the pay gap over the 20-year period. In addition, our analysis found that differences in the use of leave without pay and breaks in federal service accounts for little of the pay gap for this group. The portion of the gap that we could not explain increased over time from 2 cents in 1998 to 9 cents in 2007. However, the results of the 1988 cohort are not necessarily representative of other cohorts. Ultimately, the gender pay gap for the entire federal workforce has declined primarily because the men and women in the federal workforce are more alike in characteristics related to pay than in past years. We cannot be sure why a persistent unexplained pay gap remains for both our analyses, but this may be due to the inability to account for certain factors that cannot effectively be measured or for which data are not available.