Much attention has been given to Sheryl Sandberg’s new book, “Lean In: Women, Work and the Will to Lead,” and the potential impact it could have on the career paths of women. The book spawned the creation of LeanIn.org, a nonprofit organization that’s committed to offering women the ongoing inspiration and support needed to help them achieve their goals. Sandberg, COO of Facebook, donates all of the profits from her book to LeanIn.org, as well as covers the operating budget for the nonprofit organization.

But is this push to promote women in the workplace working? The early returns are in, and the results aren’t promising. Women hold only 11.5 percent of the board director and highest-paid executive positions at the 400 largest public companies with headquarters in California, according to a UC Davis Graduate School of Management study released last week. What’s more discouraging, that represents just a half of a percentage point increase over the prior year, and a virtual flat line trend during the decade that the school has been tracking the representation of women in these positions.

Furthermore, Sandberg’s own industry is particularly egregious when it comes to women representation at the top levels of management. According to the UC Davis report, Silicon Valley technology companies (there were 107 total in the report) average only 11 percent of female board directors and 8.1 percent women in highest-paid executive positions, among the lowest representation in the state.

“We cannot grow impatient,” said Ann Huff Stevens, a professor of economics and dean of UC Davis Graduate School of Management, and Amanda Kimball, author of the UC Davis Study of California Women Business Leaders, in this article they wrote for the San Jose Mercury News. “The Lean In movement has highlighted the need to encourage and assist women to take a seat at the table. Careful and ongoing monitoring of firms’ and women’s progress can help sustain this momentum. Advocacy groups can provide women with the skills and connections they need to be prepared for leadership roles.”

Of the “California 400” studied in the report, more than a quarter of them (101) have no women on their board of directors or among their highest-paid executives. Progress must be made in changing the thinking and culture at the top of corporate America. Not only does it make marketing sense to want to get the opinions and insights of a more diverse group, but it’s been proven to make financial sense as well — a true win-win for women and their employers.