*CORPORATE -WOMEN- CALLINGS*

WOMEN IN BUSINESS start out equal to men in terms of jobs and pay. But at each level, they disappear. Only 22 percent of senior vice presidents are women.

And of those, just 21 percent have roles relating to generating revenue, which generally lead to C-level jobs, according to the annual Women in the Workplace study by Lean In and Mckinsey.

The drop-off starts with the first promotion to management. Women are 18 percent likely to be promoted to manger than their male peers.

''MEN AND WOMEN are all going into high-powered jobs,'' said Robin  Ely, a professor at Harvard Business School and chairwoman of its gender initiative.

''The question is what happens to them down the road, and that's a messy story. People say they are opting out, they want work-life balance, but we know from a lot of research that it's not as simple as that. They are not given opportunities.''

ONE OF the main explanations of women's under-representation has been that it's too hard to run a big company and be a mother. But it's increasingly clear that this explanation overlooks deeper issues about the way workplaces operate, some experts say.

For one, men have families too. By making caregiving a women's problem, companies avoid changing their cultures in ways that would give everyone more work-life balance - for example, by limiting after-hours work or offering more flexibility about when and and where work gets done.

Instead, women are much more likely to use workplace policies like parental leave, to work part time or to move in less demanding positions because of their family obligations.

Men are just as likely to say that they're stressed about juggling their careers and family life, but they deal with it differently.

They leave early, ask colleagues to cover for them or take local clients that don't require travel - but tend not to tell anyone they're doing it.

The result is that women's career are stunted, but men's are not.

The Honor and Serving of the latest Global Operational Research on Women, Corporations and the state of the world continues to Part 3. !WOW! thanks author and researcher Claire Cain Miller.