Nearly three decades ago, I joined a regional U.S. bank as a young economist. At orientation, I checked the box for "officer" because I was interested in being part of the bank's Officers Club.

The person handling the orientation didn't believe I was an officer. She said she had to check with her supervisor to confirm my position and conceded only when I showed her my offer letter, which clearly designated my ranking.

I was recently reminded of this when I saw that American Banker was again hosting its annual gala honoring the most powerful women in banking and finance. It's true that there are powerful women in banking and financial services firms. Women have made great progress. But the picture is mixed at best.

On the upside, women are now entering the banking industry in greater numbers than ever before, according to figures from the U.S. Bureau of Labor Statistics analyzed by Catalyst. They have made major progress in middle management and in banking's "softer" areas, such as human resources and diversity and inclusion as well as the risk function.

However, women's numbers drop dramatically between the mid-manager level and the executive ranks, while men's representation soars. A mere 26% of women hold executive or senior-level positions, as the U.S. Equal Employment Opportunity Commission reported in 2011.

Many factors contribute to this discrepancy. Based on observations from my 30-year career in financial services, male chief executives appear to be less willing to take risks on women. Men are still promoted to senior roles based on their perceived potential. Women, however, are promoted based on experience. Women are therefore required to prove they can succeed in a certain role before they can be promoted to it — a Catch-22 that few are able to overcome. And a perceived lack of clarity about the factors used to select future leaders also discourages some women from aspiring to such roles, according to a study by PWC, "Minding the Gender Gap."

Outright discrimination can also play a role. A third of women in U.S. financial services firms say they have faced discrimination, according to a 2014 survey by eFinancialCareers.

Research shows that high turnover rates among women could also be a contributing factor to the lack of women in executive roles. Staff churn as women reach child-bearing age means that promising female talent is taken out of the leadership pipeline. Women who become mothers may also have career gaps that make it more difficult for them to reach senior-level positions.

Given these obstacles, what can be done to help women in banking achieve their full potential?

Some suggest that the gender imbalance in the financial industry might be corrected by setting boardroom quotas for women. But this is not the right way forward. Quotas would only serve to damage efforts by women to rise on merit. When companies have quotas, women who are promoted to prominent positions often find that their peers assume they are "tokens" with weaker qualifications than their male counterparts.

Promotions based solely on gender depreciate the hard work and talent demonstrated by working women in the financial services industry. They only serve to foster prejudice about women's ability to reach the most senior banking positions. Furthermore, filling senior roles based on quotas is bad corporate governance.

Flexible hours and the possibility of remote work are other frequently-cited solutions to closing the gender gap. These changes could indeed help many women, although it's important to note that they would also help men with care-giving responsibilities as well.

On a broader level, the banking industry needs to take the initiative to clarify and open career trajectories to women. Performance should be measured as much as possible in metrics that concrete and readily tracked, and the promotion process should be more transparent. The criteria necessary to progress to leadership positions should be publicized. And the senior men now in power should take it upon themselves to actively coach and sponsor promising female leaders.

In addition, senior female executives need better visibility as role models for other women who aspire to higher positions. This puts an extra burden on women leaders to reach out and mentor younger women in the workplace. But that is a task most women leaders are happy to undertake.

Greater gender equality makes good business sense. A 2014 study by Catalyst showed that Fortune 500 companies with the highest representation of women had 35% higher return on equity and 34% higher total return to shareholders. Several separate studies have shown similar statistics, including USA Today, which compared the stocks of 13 Fortune 500 companies with women CEOs to the stocks of the overall S&P 500. The study found that the women-led companies were up an average of 50%, while the S&P 500 was up 25%.

Nearly three decades have now passed since I was asked to provide documentation to prove my officer status. When I look at the dynamic and inspiring women in leadership positions on boardrooms and executive suites across the financial industry, I reflect on how far we've come. But the fact that they remain far outnumbered by men is a reminder of how far we still have to go.

Shaheen Dil is a managing director with Protiviti and leader of the firm's data and analytics practice.