**FILE** In this Nov. 15, 2005 file photo, a woman exits an Avon store in New York. Cosmetics company Avon Products Inc. said Tuesday, April 29, 2008, its first-quarter profit rose 23 percent as international sales, particularly in Latin America, offset declining North American revenue. (AP Photo/Gregory Bull, File) (Gregory Bull)

What was unusual is that the company is keeping Jung in the executive chairman role without immediately naming her successor. Typically, companies treat such a move upstairs as a pseudo-retirement or as a way to usher in new talent while retaining the experience of the departing CEO. While the company told the Wall Street Journal it was Jung’s idea to separate the roles, and Jung will retain the two jobs until a replacement is named, the fact that they did so before a successor is in place makes it look a lot like they’re trying to show Wall Street they’re ready for new leadership.

Jung’s pending departure from the CEO role will cut short the longest-serving tenure of a female CEO in the Fortune 500 and diminish the ranks of women in the CEO role even further. That’s particularly notable given today’s news from the nonprofit Catalyst, which studies women and leadership roles. On Wednesday it released its annual census of female executives, top earners and board members in the Fortune 500, and the study shows that women have made no significant leadership gains in Corporate America in the past year.

The news will look even grimmer following Jung’s departure. Women held 14.1 percent of executive officer positions in 2011, a number that’s already lower than it was in 2010, at 14.4 percent. Women held only 7.5 percent of top earner positions in 2011, virtually unchanged, and even slightly worse, than the 7.6 percent in 2010. Not even one in five companies had women in 25 percent or more of their C-suite roles, according to Catalyst, and more than one quarter of companies in the Fortune 500 have zero women in executive officer jobs. One in 10 companies still have no women serving on their boards.

This is not to say that Jung’s departure might not be warranted. She has been under fire with investors for some time, and after news hit about the SEC inquiries and the company’s third-quarter results in October, analysts didn’t hold back. In a conference call, Stifel Nicolaus analyst Mark Astrachan asked why investors should “believe management and board have any control over the business at this point.” Another went so far as to say that “it strikes me that you guys are so totally screwed up in so many ways the change has to be radical.”

Such radical change would be extraordinarily difficult for any incoming CEO. But it will be particularly so if the very person who ran the company for the past 12 years is looking over his or her shoulder from the chairman’s perch. Perhaps Jung is the sort of hands-off manager who won’t mess with her successor’s ideas—the company seems to be positioning this as a long-term move. And perhaps her replacement will be the type who can do what needs to be done even with Jung as chairman of the board. But such a set-up seems unsustainable over the long haul. Even with the best of personalities in place, it may not be long before it’s not just the ranks of female CEOs that lose a name, but the ranks of female executive chairmen, too.

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