The old adage “a woman’s work is never done” isn’t quite true. Everything after her approximately 92-hour work week is free time, according to a Salary.com survey.

Surveying over 40,000 moms who kept track of their hours, Salary.com estimated that they work an average of 92 hours a week—that’s 40 hours base pay and 52 hours overtime—wearing 10 different hats: housekeeper, day-care center teacher, cook, computer operator, laundry machine operator, janitor, facilities manager, van driver, ceo and psychologist.

Mothers who work outside the home log 49 hours a week on mom duties at home.

Add up all the jobs of a stay-at-home mom, pay her the going hourly rate, and she’d be pulling in a handsome salary of $138,095 a year, Salary.com says.

That website has a little fun with these statistics, offering users the chance to print off “pay stubs” for their moms as a Mother’s Day gift. (This feature, along with complete survey results, can be found at http://mom.salary.com.) But the reality behind the numbers is worth contemplating.

Consider how much greater the quality of life is for the family members whose mother dedicates herself full time to them. Most families choose instead to have the extra income the woman can bring in by working outside the home. But of course, the improved standard of living made possible by the higher income stream is offset by the hours sucked out of the home, not devoted to the family.

It is indeed impossible to put a price on just how much a dedicated, full-time mother adds to the life of her husband and children. Read our article “The Beautiful Role of a Mother.”