April 10 marks Equal Pay Day, the day that women would have to continue working to in order to earn the same amount men earned in the previous year, on average.
That goes for white, non-Hispanic women and men. For black women, it would take until August 7 to reach equal pay. For Latinx women, it's November 1.
Earning less can have a lasting impact. Women aren't just losing out on wages, but have less freedom to save and invest for the future. And thanks to compounding interest rates, even a slight difference in the amount they invest now can add up to major discrepancy down the line.
"It's clear — and unfortunate — that the pay gap can quickly become a wealth gap," Arielle O'Shea, investing and retirement specialist at Nerdwallet, tells CNBC Make It. "It's simply much harder to find the money to invest on a lower salary, and consequently women stand to lose out on investment returns over time."
To illustrate how much money women would have if they invested the money lost to the pay gap, NerdWallet compiled a chart showing the how much it would add up to after one, three, five and 10 years.
If women had been able to invest the $10,086 less they earn on average over 10 years, they would accrue $49,140 just from interest alone, assuming a 6 percent rate of return. In total, it would amount to a $150,000 boost to a retirement account.
Projecting even farther into the future, that number only expands. Over 40 years, investing $10,086 per year at a 6 percent rate yields $1.8 million, before taxes and inflation.
While these numbers are hypothetical — it's impossible to predict the future of the market or a woman's earning potential — it provides a startling look at how the wage gap can cost women far more than it appears at face value.
"The hard reality is that women need to save a greater percentage of their income to accumulate enough money for retirement," O'Shea says. "To build an equivalent retirement nest egg, on average, women must save $1.25 for every $1 a man saves."
To see if you're on the right track, O'Shea suggests using a retirement calculator, such as the one NerdWallet offers.
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