It's Equal Pay Day. It symbolizes how much longer a woman had to work into the next year to make as much as a man did the year before.
The gender wage gap is something advocates and some businesses have been trying to close for a while.
But some companies say they've reached 100 percent pay equity.
In 2016, Apple said it established equal pay across the board. It also said that every year, it adjusts employees' pay to reach that goal.
In 2017, Intel announced it reached 100 percent pay equity for women and underrepresented minorities. The company said it also reached promotion parity.
And in March, Starbucks said all genders and races would receive the same pay for doing similar work.
But while some companies have made pay equity a priority, in 2017, women in the U.S. still made about 82 percent of what men did for the same job, according to the Pew Research Center.