Despite earning more college and graduate degrees than their male counterparts, the Institute for Women's Policy Research (IWPR) reports that women still earn 80 cents for every dollar earned by a man.
According to data from IWPR, if the same pace towards pay equality continues, women will continue to be outearned by men until 2059. For women of color, that pace is even slower: Hispanic women will have to wait until 2248 to reach pay equality and Black women until 2124.
Unequal pay has the greatest affect on women who earn the least. But celebrities like Oprah Winfrey, Venus Williams and others in sports and entertainment are also taking a stand in the fight for equality, emphasizing that that gender discrimination persists across industries and socioeconomic tiers.
In a TIME special report highlighting women who are breaking glass ceilings in their respective industries, Oprah Winfrey recalled a time she noticed gender discrimination at work and how she addressed it.
After "The Oprah Winfrey Show" gained national syndication, Winfrey said she went to her boss and asked that her producers receive a raise.
Her boss's response: "They're only girls. They're a bunch of girls. What do they need money for?"
Reflecting on her days as a news anchor in Baltimore — when she knew she earned less than her male co-anchor — Winfrey decided to take a stand to ensure that her staff was paid equally.
She says she told her boss, "Either my producers are going to get raises or I'm going to sit down. I just won't work. I will not work unless they get paid more money."
Winfrey's decision to speak up paid off, and her boss eventually gave her staff the money she felt they had earned.
In 1998, just days after her 18th birthday, Venus Williams spoke to the press after her first-round match at Wimbledon to address the unequal prize money that female athletes received compared to their male counterparts.
"I think in the Grand Slam events, it should be equal pay, and I think the ladies should do something about it instead of just accepting it for years to come," she said.
A day after winning the Wimbledon title in 2005 against Lindsay Davenport, Williams attended a board meeting held by the All England Lawn Tennis and Croquet Club at which she spoke to leaders of the organization about the pay gap. A year later, Williams was approached by Larry Scott, CEO of the Women's Tennis Association, to help continue to push the issue of equal pay forward.
"The message I like to convey to women and girls across the globe is that there is no glass ceiling," Williams wrote in an op-ed for The London Times. "My fear is that Wimbledon is loudly and clearly sending the opposite message."
The editorial gained much attention, and Tim Phillips, chairman of the All England Club, wrote in a statement in 2007 that the time was right to "eliminate the difference" in prize money.
Filmmaker Ava DuVernay highlighted the tennis star's work in the 2013 film "Venus VS."
In 2015 Patricia Arquette made headlines when she used her Oscar acceptance speech to spark a conversation among Hollywood's elite about equal pay.
"To every woman who gave birth to every taxpayer and citizen of this nation, we have fought for everybody else's equal rights. It's our time to have wage equality once and for all, and equal rights for women in the United States of America," she said.
Stirring up a string of reactions on social media, Arquette maintained her stance, tweeting further thoughts about the issue following the awards.
"Guess which women are the most negatively [a]ffected in wage inequality?" she tweeted. "Women of color. #Equalpay for ALL women. Women stand together in this."
A year after her speech, Arquette co-hosted a "Dinner for Equality" along with Salesforce CEO Marc Benioff, at which she told Variety that she had lost two acting jobs since speaking out about equal pay.
"It's not just about acting, and it's not about me as an actor," she said. "I don't believe this is fair for anybody. I want to live in the America I believe in, that really is fair, that really has possibilities, and really does treat people of all races and all sexes equally."
In 2004, as a U.N. Women Goodwill Ambassador, Emma Watson addressed issues of gender discrimination during a speech at the organization's headquarters in New York.
"I am from Britain and think it is right that as a woman I am paid the same as my male counterparts," she said. "I think it is right that I should be able to make decisions about my own body. I think it is right that women be involved on my behalf in the policies and decision-making of my country."
In Esquire U.K's 2016 "Women and Men" issue, Watson discussed the topic of equal pay again.
"There's a willingness now to be like, 'Fine. Call me a 'diva', call me a 'feminazi', call me 'difficult', call me a 'First World feminist,' call me whatever you want,' it's not going to stop me from trying to do the right thing and make sure that the right thing happens," she says.
In a 2013 interview with GQ, Beyoncé spoke about why women should not settle for making less than men.
"You know, equality is a myth, and for some reason, everyone accepts the fact that women don't make as much money as men do. I don't understand that. Why do we have to take a backseat?" she says.
The following year, she wrote an essay for The Shriver Report in which she called on men to fight for women to earn equal pay for equal work.
"Men have to demand that their wives, daughters, mothers and sisters earn more — commensurate with their qualifications and not their gender," she wrote.
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