The wage gap between black and white Americans has persisted for the past half century. In 1967, black families had a median household income of $24,7000, while white families earned a median income of $44,700. By 2014, the median household income for black families had increased to $43,300, but white families earned a median income of about $71,300.

At the same time, the number of hours worked in the past 40 years increased, a report published Wednesday by the Economics Policy Institute found. And the increase in hours worked was larger for blacks than for whites.

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To  lay out the findings clearly:

  • In 1979, the average black worker logged 1,606 hours total. The same year, the average white worker logged 1,701 hours.
  • In 2015, the average black worker logged 1,805 hours. The average white logged 1,888 hours.
  • The number of hours worked by the average black worker increased by 12.4 percent. The number of hours logged by the average white worker increased by 11 percent.

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The difference in those numbers was even starker when taking into account gender and socioeconomic income: Black women in the bottom fifth bracket of the income ladder saw an increase of 30.1 percent in work hours from 1979 to 2015.

In comparison:

  • White men in the bottom fifth of the economic ladder saw their work hours increase 3.2 percent from 1979 to 2015.
  • Black men on the bottom fifth rung of the ladder increased their work hours by 7.5 percent from 1979 to 2015.
  • White women in the same socioeconomic bracket saw their work hours increase 27.6 percent from 1979 to 2015.

“The data make it clear that there has been no lack of effort on the part of black workers,” the report states. “Even in the face of persistent racial wage gaps, labor market discrimination, occupational segregation and other labor market obstacles, black workers continue to increase their annual hours and weeks worked per year.”

Here’s the full data, broken down by race, gender and income:

economic policy institute Growth in work hours and real wages, by race, gender and wage group, 1979–2015. Photo: Economic Policy Institute