Have you ever wondered why so few women populate the top ranks of large banks?

Women and men enter the banking business in roughly equal numbers and get promoted to mid-management at nearly the same pace. But fewer women clear that next rung, into senior management, and only a tiny fraction have an office in the C-Suite.

There are lots of reasons and plenty of research on this question, but one big factor it seems to me is that women lose hope. They see how few women make it into banking's inner circle, and they give up.

Let's take a look at the facts.

At the six largest U.S. banks by asset size, just 12 of the 82 people who comprise the executive teams are women. (And a third of those women do not run line businesses, which arguably makes them weaker players among the power set.) If you add in the two big investment banks, the tally gets worse: 14 women among 106 executives.

There is only one woman on the executive team at JPMorgan Chase, at Citigroup, at PNC, at Goldman Sachs and at Morgan Stanley. Two women have cracked that barrier at USBank.

Of the tens of thousands of people working at those six giant firms, only seven women are qualified to be a member of the CEO's inner circle? That's not only impossible, it's unacceptable.

Bank of America and Wells Fargo stand out by comparison.

BofA has four women on its 11-member executive team. Three of the 12 people on Wells Fargo & Co.'s executive team are women.

The solutions vary but one way to get more women in the C-Suite is to get more women on bank boards of directors.

It's simple. If you are a CEO with a predominantly male inner circle and a board with a significant number of women you are going to try a little harder to find some women to join your team.

Let's take a look at the top-six U.S. banks' boards. Guess which one was the most women?

That's right – Bank of America. Is it a coincidence that the bank with the most women in senior management also has the most women on its board? Four of 16 directors at BofA are women.

The story repeats itself at Wells Fargo. Five of the 15 people on its board are women.

The story is a little more mixed when you look at the board make-ups at JPMorgan, Citi, PNC, USBank, Goldman and Morgan Stanley.

Just two of 11 board members at JPMorgan are women. Three of 15 directors are women at PNC and three of 14 directors are women at USBank. At Citi, three of 12 directors are women. At Goldman and Morgan, each has two women on their board. At Goldman it's two of 10 directors; at Morgan Stanley it's two of 14.

If these companies had more women on their boards, I think it's an easy bet their CEOs would make it a priority to have more women on their executive teams.

This idea is illustrated starkly by two banks of similar size in similar markets: SunTrust Banks in Atlanta at $170 billion of assets and BB&T in Winston-Salem., N.C., with $164 billion of assets.

SunTrust has just one woman on its 14-member board and unsurprisingly it has one woman on its 11-member executive team. But look at BB&T. Four of its 15 directors are women and three of its 12-member executive team are women.

It's been 10 years since my company started recognizing the women who beat the odds and succeeded in the male-dominated banking industry.

Much progress has been made in that decade. Beth Mooney became the first female CEO of a top-25 U.S. bank and a number of women have reached the top management tier of large foreign banks with operations here like Irene Dorner, the CEO of HSBC USA, who was this year'sMost Powerful Woman in Banking.

In her acceptance speech at a dinner on Oct. 16, Dorner tackled this question of the lack of women in senior management.

The stubbornness of the status quo, she said, is supported by unconscious bias. It's human nature for people to hire others who are like them, and since banking is led by men, more men lead banks.

Women, like herself, who have succeeded in this business did so largely by playing the game by the guys' rules. But "bending yourself out of shape uses up emotion and energy… it's why people leave, and contributes to the fact there are so few women at the top," Dorner said.

Dorner wrapped up her speech with a call to action.

"More of what we have done will not get us where we want to be. So let's have some change," she said. "Let's have that meritocracy, the best people in the right jobs but chosen from a balanced and level playing field…

"Do more to create a level playing field for women… Do it because meritocracy is a step towards renewing our industry. Do it because there are a lot of women out there who can get us where we want to be. And do it because it's right."

Dorner then appealed directly to the powerful women in her audience.

"Push back on that status quo and just don't accept the old rules. Speak up about what you want. Believe and encourage others to do the same and lead by example.

Be authentic. Remember our careers would have been better if meritocracy were embedded in the workplace when we started out.

"As for the long-term, insist that reward and promotion are based on merit. Reinvest your success. Pay it forward through mentoring and coaching. Champion those who deserve greater recognition but who like you and me didn't fit in.

"I believe women can lead the way in rewriting the rules of the workplace and restoring the good name of the banking industry."

It was an inspiring speech. A standing ovation followed. But is Dorner's prescription it enough? I'd love to think "do the right thing" would resonate in this industry and change would follow.

But I fear that's idealistic.

Change is more likely to occur if we set goals and measure progress.

I don't support government-mandated quotas. Washington already has a heavy-enough hand in how financial companies are run.

But imagine the benefits if the financial services industry decided to set and achieve voluntary diversity goals? Imagine if the industry announced it would try and seat women or minorities in at least a third of all directors' seats over the next few years?

In addition to better, more balanced decision-making, the industry would be viewed as a leader on gender diversity.

And it could certainly use the good PR right now.

Think about it.