Only one major company earned an 'A' on the Gender Pay Scorecard

Only one major company gets an "A" grade when it comes to gender pay equity, and that's Citigroup (C).

That's according to the Gender Pay Scorecard report co-authored by Natasha Lamb, a managing partner at Arjuna Capital, and Michael Passoff, the CEO of Proxy Impact.

The second annual report released ahead of Equal Pay Day, ranks 47 companies from the banking, technology, and retail sectors based solely on quantitative results, not "qualitative assurances." The grades were calculated using five categories, including adjusted "equal pay" gap, unadjusted median pay gap, racial pay gap, coverage, and commitment.

The reason Citigroup tops the list is that the bank started reporting its gender pay gap, not just on equal pay for equal work basis, but on a median basis that shows whether employees have an equal opportunity. In January, Citigroup said that the median pay for women globally is 29% less than men, and the median pay for U.S. minorities is 7% less than non-minorities.

"[Citigroup] was the first to voluntarily disclose that number both for gender and race in January and really has set a new standard for disclosure going forward," Lamb told Yahoo Finance.

Nine companies, including Apple (AAPL) and Starbucks (SBUX), earned a "B" grade this year, while 23 companies, including Goldman Sachs (GS), Walmart (WMT), and Oracle (ORCL), received an "F."

Goldman's new CEO David Solomon recently set mandates to promote gender and racial diversity at all levels of the firm, including the upper echelons. He said that business unit heads would be held "accountable" for progress toward these goals.

"I think it's incredibly important that the tone from the top is one promoting diversity and equal opportunity," Lamb said. "It's important from the investor perspective that it's not simply lip service."

While Lamb hasn't engaged with Goldman directly, she wants to see quantitative numbers on equal pay, median pay, and racial pay.

"It's all well and good to say that you want more diversity in leadership, but there needs to be transparency, accountability, and goals moving forward."

Lamb has made a name as a formidable activist shareholder when it comes to promoting gender and racial pay equity. Of the 47 companies graded, Lamb's firm Arjuna has actively engaged with 23 of them.

Julia La Roche is a finance reporter at Yahoo Finance. Follow her on Twitter.

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