NEW YORK (CNNMoney.com) - The rate of home ownership for low- to moderate-income families with children is lower than in 1978, even as the overall rate of home ownership increases, according to a study from the Center for Housing Policy released Wednesday.

The study found that only 59.6 percent of working class families owned their homes in 2003, the most recent year for which figures were available, down from 62.5 percent in 1978.

Meanwhile, home ownership in the overall population has risen to 68.3 percent in 2003 from 65.2 percent in 1978. The study is based upon Census Bureau data.

According to the Center, that translates into 2.3 million children who would be living in owner-occupied housing if the rates had remained the same.

The study defines working class families are ones whose earnings range from $10,700, or the equivalent of working 40 hours a week at minimum wage, and up to 120 percent of the median income in their area.

The study cites a combination of factors for the divergent trends, including soaring housing costs that have overshot wage increases, higher health care bills and a rise in the number of single parents.

Barbara Lipman of the Center for Housing Policy, the research arm of the National Housing Conference, a housing affordability advocacy group, told the paper that the trend likely has persisted since 2003 in the face of sharp increases in real estate prices and more modest gains in earnings, particularly among low wage jobs.

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