The salary penalty for hopping off the career track is even higher in the business world, where earnings drop an average of 28%, according to the survey by the New York-based Centre for Work-Life Policy on Wednesday.
  
The drop in pay partly reflects many women's decisions to return to work in jobs with less responsibility, or to part-time jobs.

But it may also reflect that women are exiting the workforce during the years when many men make the largest leaps up the corporate ladder, the survey's authors conclude.
  
The price for exiting work steepens the longer women wait before returning. Women who take less than a year off from their careers, return to the labour force at an average of 11% less pay.

But those who take off for three years or more return to pay averaging 37% less than what they originally earned, according to the survey.
  
The research is detailed in the March issue of the Harvard Business Review.

Survey stats

The survey tapped more than 2400 women, focusing on those with a graduate degree, professional degree or undergraduate degree with high honours. The group also surveyed 653 similarly qualified men as a means of drawing comparisons.
  
The notion that more executive women are choosing to exit the workforce has generated considerable attention over the past year in business circles. The survey, done this past summer, is one of the first efforts to try to verify and explain women's choices.
  
"Relatively short career interruptions entail heavy financial penalties," Sylvia Ann Hewlett and Carolyn Buck Luce, leaders of the task force that authored the study, write in the magazine.

"The longer you spend out, the more severe the penalty becomes."