Why 2018 could be a record year for women joining corporate boards

Women are on track to gain a record number of board seats by year's end, the Wall Street Journal reports.

From January to May, women made up 31 percent of new board directors at 3,000 of the largest publicly traded U.S. companies, according to a data analysis by corporate governance firm Institutional Shareholder Services. That's the highest percentage of female board seats in at least a decade.

Some notable 2018 board selections include those made by collaboration platform Slack, which appointed Edith Cooper to its board in February, and beauty company Estée Lauder, which added two female board members in April for a total of eight women on its 17-person board.

This increase in female board representation shouldn't be all too surprising, given a growing body of research showing that diverse boards improve business performance, as well as the gender inequality issues that have plagued companies over the last year.

In August, a 10-page manifesto by a former Google employee sparked national outrage and brought the opposition women face in the male-dominated tech industry into the spotlight once again.

Months later, women galvanized to share their experiences dealing with workplace sexual harassment. The ensuing #MeToo movement led to the toppling of prominent businessmen like Steve Wynn, the founder of Wynn Resorts. In April, the hotel chain added three women to it's board in an effort to refresh the brand after Wynn resigned as CEO and chairman.

Companies are also feeling pressure to diversify their boards from large investment firms, who see a positive correlation between diverse board selection and greater financial returns.

BlackRock, which has taken an increasingly activist approach to how the company does business, recently urged its portfolio companies to up the number of women on their boards.

"We would normally expect to see at least two women directors on every board," the financial behemoth said in a set of proxy voting guidelines published to its website in February.

The effectiveness of these investor demands can be seen with Amazon, whose leadership has historically lacked female representation. In April, the retail giant pledged to include women and minority candidates in their board candidacy pool, following shareholder complaint.

But it's not all good news. The ISS data found that companies have not promoted women at the same rate into leadership board positions, even though they come in with greater qualifications than their male counterparts.

Even more troubling, about a dozen of the largest U.S. companies have yet to add even a single female director to their board, according to a previously reported analysis by Equilar and CNBC.

To combat statistics like these, some are pushing for quota systems that would require equal gender representation on boards. A number of European countries have already adopted this strategy for company boards, including Germany, Norway and France.

But these mandatory targets have yet to catch on in the U.S. Some states have adopted nonbinding resolutions, pushing companies to diversify their leadership teams. The California state legislature is considering a bill which requires that publicly-held corporations add at least one woman to their board.

In a CB Insights panel on Thursday, Ellevest CEO Sallie Krawcheck said that while she has opposed gender-related quotas, she might one day change her mind, and feels they're "underrated."

"Our progress on getting more women on boards has been sluggish at best, despite all the research that shows it can drive superior performance," she tells CNBC Make It. "So at some point, it may make sense to acknowledge that what we're doing now simply isn't working."

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