Slow progress for women leaders in corporate America

New research shows that the number of women executives is heading in the right direction, but at a very slow pace.

FORTUNE -- Slooowww progress is the headline this morning  from research group Catalyst, which released its annual gender report on Fortune 500 companies and boards.

Here are the key takeaways:

- 16.6% of Fortune 500 company directors are women, up from 16.1% last year.

- 14.3% of Fortune 500 company executive officers are women, up from 14.1% a year ago.

- 8.1% of top earners in the Fortune 500 are female. That's up from 7.5% in 2011.

You won't find much to inspire you in the Catalyst report. But one bright spot not noted there: The number of female Fortune 500 CEOs will hit a record 21 on January 1 when Phebe Novakovic takes charge at General Dynamics (GD).

And don't pop the champagne, but we now have two--two!--Fortune 500 companies that have more women than men in their executive officer rankings.

One is Ingredion, until this year known as Corn Products International. Ingredion's CEO is a woman. Ilene Gordon, the former chief of Alcan Packaging, took charge in 2009 and rebuilt Ingredion's product portfolio and leadership team. Five of the company's 11 top officers are now women. It's working. Revenue exceeded $6.2 billion last year and the stock has been outperforming the S&P  since Gordon arrived. Ingredion (INGR) shares are up 27% in the past year.

The other company with more women than men at the top: Frontier Communications. CEO Maggie Wilderotter joined the telecom company, then known as Charter Communications, from Microsoft (MSFT) in 2004 and refashioned the board and the company's direction. Her market is rural telecom, which she has invested in aggressively by buying Verizon's (VRZN) rural assets. Wilderotter is a big player—on the boards of Procter & Gamble (PG) and Xerox (XRX)--and the sister of another Fortune 500 CEO, Denise Morrison of Campbell Soup (CPB). But her own return to investors is disappointing: Frontier (FTR) shares are down almost 9% this year and 59% over five years.