WASHINGTON -- For a woman with three houses and sixteen grandkids, Ann Romney doesn't have very much help around the house, according to her 2010 tax return.

IRS forms released Tuesday by Mitt Romney's presidential campaign show that despite reporting income of $21.7 million, the couple paid only $20,603 in taxable wages for household help in 2010. This figure was divided among four women: Rosania Costa ($4,808), Kelli Harrison ($8,667), Susan Moore ($2,238) and Valerie Cravens Anae ($4,890).

According to a number of Boston-based domestic staffing agencies, the salary range for a housekeeper is between $20 and $30 an hour, which adds up to an annual salary of $40,000 to $50,000 based on forty-hour weeks and two weeks of paid vacation a year.

But this number is only for one house, and the Romneys have three houses -- a 2,000 sq. ft. townhouse in Belmont, Mass., a 5,400 sq. ft. lake house on 11 acres in Wolfeboro, N.H., and a beach house in La Jolla, Calif., that is undergoing renovations to double its size.

Even if the Romneys avoided spending time in La Jolla in 2010, they spent plenty of time in New Hampshire, with regular visits in the summer from five sons and their families.

Yet the Romneys still paid only half of the lowest range of an average housekeeper's salary, which raises the question of who cleaned the Romney houses the other 50 percent of the time. A Romney campaign adviser declined to respond to questions from The Huffington Post about the housekeeping salaries.

Wouldn't it be nice to learn that the Romneys split up household cleaning between them on days when the housekeeper was out? After all, Mitt Romney was "unemployed" in 2010, as he infamously reminded a group of voters in Tampa, so he had some extra time. And Mitt even knows how to do laundry, according to a photo tweeted Monday by his son Tagg Romney.

The more worrisome alternative is that the Romneys underpaid their household help.

The Massachusetts Coalition of Domestic Workers holds a meeting on the third Tuesday of every month to work towards passage of a statewide Bill of Rights for domestic workers, but so far their efforts have fallen short.

UPDATE: 5:27 p.m. -- At least one of the four women paid for domestic work by the Romney family in 2010 also worked as chief of staff to the executive director of Mitt Romney's Free and Strong America PAC at the same time.

Kelli Harrison was paid wages of $8,667 by the Romneys for personal assistant-type tasks and errands, said a source with knowledge of the situation. Harrison was the most highly paid of the four women listed as domestic employees of the Romney family, and the other three women did not work for the Romney PAC at all, the source confirmed. Harrison was paid for her PAC work with PAC funds.

The designation of household employees is broad, and can include housekeepers, baby-sitters, personal assistants and other house-related tasks. It's possible that the Romney's hired an outside cleaning service to clean their houses and that managed the payroll, but the campaign declined to elaborate on their arrangement. Given the private nature of jobs like these, most high-profile individuals prefer to maintain their own staffs of people who know them well and who they trust.

Another employee, Valerie Cravens Anae, may be the same woman whose Facebook profile indicates that she attended the Mormon-affiliated Brigham Young University. Anae was paid $4,890 in taxable wages for domestic work at the Romney house in 2010.

The campaign declined to specify whether Harrison was still working for the Romney family personally. The other two women listed as domestic employees, Susan Moore and Rosania Costa, could not be located.