SAN FRANCISCO (CBS SF) — Thirty-one U.S. senators are demanding that the U.S. Soccer Federation pay players on the Women’s National Team the same as their heavily-compensated male counterparts.

The U.S. Senators, including U.S. Senators Dianne Feinstein and Barbara Boxer, both Democrats representing California, wrote in a letter addressed to U.S. Soccer Federation President Sunil Gulati on Wednesday, urging him to ensure that members of the U.S. Women’s National Team (WNT) are paid the same as men.

The letter to Gulati comes after five members of the World Cup-winning WNT alleged in a federal equal-pay complaint to the Equal Employment Opportunity Commission in March that they were paid substantially less than their male counterparts in the under-performing U.S. Men’s National Team (MNT).

The senators said they were shocked and appalled by the vast gender pay gap that top-tier professional female soccer players in America are experiencing when compared to their male counterparts.

The senators quoted the EEOC complaint, which states that “a 20-game winning top tier [Women’s National Team] player would earn 38% of the compensation of a similarly situated [Men’s National Team] player.”

U.S. Senator Dianne Feinstein took to Twitter Wednesday to publicly urge the U.S. Soccer Federation to pay fairly. She highlighted players’ documentation of  “disparities in pay, including salaries, win bonuses and daily travel allowances” between male and female soccer players on the U.S. team.

According to the EEOC complaint filed by Hope Solo, Carli Lloyd, Megan Rapinoe, Rebecca Sauerbrunn and Alex Morgan, a player on the MNT is awarded a bonus for each win ranging from $6,250 to $17,625, while a female player on the WNT is awarded only a $1,350 bonus for every win.

In July 2015, the WNT won its third World Cup title. The women’s soccer team has also brought home four Olympic gold medals and is ranked No. 1 in the world.

But despite the team’s accomplishments they still receive far less compensation than the men’s soccer team, according to the complaint.

According to the U.S. Soccer Federation’s most recent annual report, the federation had projected a combined net loss for the national teams of $429,929 for the fiscal year ending on March 31, 2016, but the federation ended the fiscal year projecting a $17.7 million net profit. The complaint alleges that profit is “thanks almost exclusively to the success of the WNT.”

In fiscal year 2017, the women’s team is projected to net about $5 million in profit while the men’s team is projected to have a net loss of about $1 million, according to the complaint.

Yet the men’s team players continue to make more money, the complaint alleges.

Both male and female players are required to play at least 20 games a year. A female player could make as little as $72,000 a year, but a male player could make no less than $100,000 a year, for the same amount of games played. 

However if a female player won all 20 games she couldn’t make more than $99,000 a year, yet a similarly situated male player can make about $263,000 in a year. The female player would receive just 38 percent the compensation that a male player who won the same numbers of games would receive.

After the 20 required games, female player receive no compensation for additional games if they lose or tie and receive only $1,350 for a win. Meanwhile, their male counterparts receive $5,000 for a loss and up to $17,625 for a win.

And the World Cup compensation appears to be no better.

“The pay structure for advancement through the rounds of World Cup was so skewed that, in 2015, the MNT earned $9,000,000 for losing in the Round of 16, while the women earned only $2,000,000 for winning the entire tournament,” the players state in the EEOC complaint.

The complaint also notes that the success of the women’s team actually means that they are playing more games, spending more hours training, traveling more and attending more media events than their male counterparts.

The U.S. senators explained in the letter to Gulati that the Equal pay Act requires employers to pay men and women equally for doing the same work.

“We urge you to resolve this dispute quickly and ensure that the U.S. Women’s National Team is fairly compensated,” the U.S. senators told the president of the U.S. Soccer Federation.

By Hannah Albarazi – Follow her on Twitter: @hannahalbarazi.