What do wage differentials tell about labor market discrimination?

With the signing of the Civil Rights Act of 1964, discrimination in employment with respect to the hiring, promotion and pay of minorities and women became illegal in the United States.1 Yet, 40 years later, earnings differentials still persist between certain minorities and white non-Hispanics and between women and men. For example, although the ratio of black men's earnings to those of white men and of black women's to white women's have increased considerably over the past 50 years, the black–white ratio was still only 78% in 2003 among men and 87% among women (Fig. 1). Hispanic–white wage differentials are larger than the black–white differential among both men and women (Figs. 2 and 3). And despite a significant narrowing in the gender gap, the ratio of women's earnings to men's was about 76% in 2003 (Fig. 4).2