In 1971, the U.S. Congress declared August 26 as Women's Equality Day, according to the National Women's History Project. The day celebrates the passage of the 19th Amendment in 1920, which granted women the right to vote. Each year, the president is requested to issue a proclamation honoring this day around the country.
While much progress has been made since the amendment was passed, women are reminded every day that there is still a lot more work to be done before equality is fully reached. A new study conducted by financial services firm Merrill Lynch and research company Age Wave found that by retirement age, a woman may have earned as much as $1,055,000 less than her male counterpart over the course of her career.
Pay disparity and common workforce interruptions, like caring for a sick parent or starting a family, contribute to this gap. Merrill Lynch and Age Wave found that one out of three mothers who returned to work after caring for a child say they took on less demanding work that came with a lower paycheck. Additionally, 21 percent say they were paid less for the same work they did previously.
Edythe De Marco, managing director and wealth management advisor for Merrill Lynch, says these numbers point to an alarming issue that needs to be addressed by both companies and by women themselves. "I think a big part of this is on corporate America, but I am also a believer that we as women can't wait for the world to change," she tells CNBC Make It. "We have to make change for ourselves."
De Marco says companies need to ask themselves why it's important to have women not only as employees, but in leadership positions. And once they understand how beneficial diversity is to their business, then they have to ask how they're treating the women they hire.
"Ask yourself, 'Is the work that I'm asking this woman to do, is it compelling? Is it satisfying? What is the compensation like? Is it on par with what the men are getting?'" says De Marco. If the answer is "no," then she says women are more likely to leave. And in the case of a woman who is just starting a family, she says that female employee may decide to leave the workforce altogether if the work is not fulfilling and if the pay does not provide enough cushion for daycare.
Beth Brooke-Marciniak, Ernst & Young's Global Vice Chair for Public Policy and Global Sponsor for Diversity and Inclusiveness, says providing women with the right amount of flexibility is also critical for closing the wealth gap and keeping women in the workforce. She says managers need to create a work environment where "women feel completely safe to manage their personal and professional responsibilities." Rather than focusing on input, Brooke-Marciniak says company leaders need to focus on output and "let women do their jobs in the way they want to do them."
Aside from hiring women, promoting women and providing flexibility, De Marco adds that companies need to do a better job of providing women with sponsorship support, so they can advance.
"The way men advance in their careers is they have sponsors," she explains. "They have someone to open the door for them, someone who will make a way for them. Historically, men have found that in the workplace and women haven't."
She emphasizes that in order to provide this support, company leaders need to invite women to more networking events outside the office. "This means, allowing women to attend a seminar or inviting women to lunches and dinners that men normally only get invited to," she says.
In addition to companies doing their part, De Marco says women also need to recognize their role when it comes to being advocates for themselves at work. To prepare for career advancement, she says women should take at least one personal finance course in college so they are armed with knowledge on how to budget, invest and negotiate. If personal finance isn't offered at their school, or if they've already graduated, she says women can educate themselves with books like "Getting to Yes: Negotiating Agreement Without Giving In" by Roger Fisher and William Ury, or "A Woman's Guide to Successful Negotiating," by Lee Miller and Jessica Miller.
"These are strategies women can own and be in control of," says De Marco. "We can say corporate America can do x, y and z, but who wants to wait and put their faith in an organization while they play catch up."
This story first appeared on CNBC.com. More from CNBC: