More than one in six Americans working a full- or part-time job also are caregivers of the elderly or disabled, according to the latest Gallup Healthways Well-Being Index survey.

And being away from work costs the economy $25.2 billion in lost productivity each year, Gallup estimates.

Gallup's telephone survey of 200,000 people, done between Jan. 2, 1010 and June 20, 2011, delineated other characteristics of caregivers who work as well.

They are more likely to be female than male. Though they fall into every age group, the largest percentage —22%--are between 45 and 65 years of age. About one in seven is between the ages of 30 and 40, or older than 65. More than one in 10 is between the ages of 18 and 29.

Ethnically, blacks and Hispanics workers are the most likely to be caregivers, at 21% and 20%, respectively, compared to 17% of white workers.

When it comes to income, only 15% of those who earn more than $90,000 annually are caregivers, compared to 21% of those who make less than $36,000 a year. Similarly, 15% of college graduates and 16% of postgraduates care for another, compared to 20% of those who have a high school education or less. In a news release, Gallup said that the disparity could be because those who are better educated and earn more tend to be younger, or because high earners can afford to hire help.

Those who do assume a caregiving role say it impacts their jobs and causes them to lose days at work. Of those surveyed, 36% reported missing one to five days each year, while 30% missed six or more days. Overall, caregivers miss 6.6 workdays every year, which Gallup estimates is an aggregate loss of more than 126 million workdays.