Alyson Hurt/NPR

President Obama speaks about the gap in pay between men and women on Friday, as he introduced a new proposal that would require large companies to disclose data about employee pay by race, gender and ethnicity. Brendan Smialowski/AFP/Getty Images hide caption

toggle caption Brendan Smialowski/AFP/Getty Images

Women stage a protest demanding equal pay for women at a 2012 rally in Miami. J Pat Carter/AP hide caption

toggle caption J Pat Carter/AP

From left: Nicholas Thomas, Rob Cooze and Mike Betson were among 18 men who won a pay discrimination claim against the University of Wales, Trinity Saint David. Ben Wright/PA Photos /Landov hide caption

toggle caption Ben Wright/PA Photos /Landov