The index, called the Bloomberg Financial Services Gender Equality Index (GEI), includes 26 public companies that are best-in-class in the financial industry in terms of providing opportunities for women. “But this is just the inaugural group,” says Angela Sun, head of strategy and corporate development at Bloomberg LP. “We expect many more [companies] to come on board this year.”

The index was created to satisfy demand from investors, a growing number of whom are looking to gender equality data to inform investment decisions, says Sun. After all, numerous studies have proven that diversity is good for the bottom line—including one 2015 report that found that women CEOs in the Fortune 1000 drive three times the returns of S&P 500 enterprises predominantly run by men.

Yet solid information on companies’ diversity and women-friendly policies remains hard to come by. The new index aims to fill that gap: The GEI lists 53 data points for each included company, ranging from number of women in the company and on its board, to length of parental leave, to provided child care and adoption services. It will also provide investors with an easy way to compare the performance of these companies with that of the market as a whole.

To qualify for the index, a company had to have a market capitalization of at least $15 billion and have at least one exchange-traded security, says Sun. If those requirements were met, the company was invited to participate in an in-depth survey detailing employment statistics, internal policies, women-friendly product offerings, and public support of women.

All of the firms that responded to the survey in its entirety—the response rate was about 50%—were included in the index, says Samantha Reiss, a member of Bloomberg LP’s strategy & corporate development team.

The index currently includes banking heavyweights such as J.P. Morgan Chase (JPM), Bank of America (BAC), and Citigroup (C), as well as major insurance and credit card companies like Metlife (MET) and Visa (V).

“Increasingly, we find that prospective employees and clients look at what kind of company we are when making decisions on working for us or awarding us their business,” writes Anne Finucane, vice chairman of Bank of America, in an email. “The Bloomberg GEI findings reflect what we have long known—the importance of women in our company, and the diversity of our employee base more broadly, is a reflection of the diversity of our clients, businesses and communities.”

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Women make up 26% of GEI company board members, compared to 12% in the overall financial services industry. A full 92% of the included companies have strategies in place to grow the percentage of women they hire, and 81% sponsor financial education programs for women in their communities.

The new index is not the first attempt to identify publicly traded companies that are leaders on gender diversity. Earlier this year, State Street Global Advisors (STT), a GEI member company, launched an ETF that invests in 125 to 150 companies with impressive numbers of women in management. In 2014, Sallie Krawcheck’s Ellevate teamed up with fund management company Pax World Management to offer an index fund of companies where women make up a large percentage of officers and directors.

However, where those funds are vehicles that investors can use put their money behind gender diversity, the Bloomberg index is simply a rich source of information—it’s up to investors to decide how to use that data. Still, understanding where companies stand on women and diversity is the first step to creating real corporate change, says Sun: “If you can’t measure something, you can’t manage it.”