Sen. Al Franken (D-Minn.) speaks in May about the Paycheck Fairness Act, which was ultimately filibustered by 46 Republican senators on June 5.

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he enduring pay gap between men and women has long been one of the most stubborn symbols of gender inequality, and in few places is that more obvious than in Congress, says Matt Berman at The National Journal. Women staffers on Capitol Hill make significantly less than their male colleagues, a disparity that is partly explained by the fact that high-level congressional jobs are often occupied by males — leaving the paper-pushing and appointment-making to the ladies. And the gap is most glaring in Republican ranks. Here, a numerical guide to Congress' gender pay gap:

$5,862.56
Average difference between male and female salaries in the House

$10,093.09
The gender pay gap among Republican House staffers

$1,473.65
The gap among Democratic House staffers

$7,277.69
Average difference between male and female salaries in the Senate

$9,805.85
The disparity among Republican Senate staffers

$4,919.46
The disparity among Democratic Senate staffers

41
Percent of House members who employ a female chief of staff

84
Percent of entry-level jobs in the House occupied by women

$0.77
Average amount women make to a man's dollar, nationally

$0.84
Average amount women make to a man's dollar, among House Republican staffers

46
Number of Republican senators (out of 47) who successfully filibustered the Paycheck Fairness Act, which would have given working women more power to sue for equal pay

Sources: The Frisky, National Journal, Slate, ThinkProgress