In addition to all the people whose homes have fallen into foreclosure since the bubble burst a few years back, millions more have been having trouble keeping current on their loan payments — and about half of those homeowners say they expect their payment problems to continue.

This is all according to a recent study by the University of Michigan’s Institute for Social Research, which found that between 2009 and 2011, 3.5% of American families (approximately 4.1 million) admitted to having fallen behind on mortgage payments at some point during that time period.

Meanwhile 1.7% of families in 2011 said they are “very or somewhat likely” to fall behind on their mortgage payments in the near future. That would mean as many as 2 million families in the U.S. could be circling the foreclosure drain.

“Our data suggest that the mortgage crisis will continue for the next few years, although a somewhat smaller share of families will experience mortgage distress” says Frank Stafford, co-author of the report. “And even though average savings levels have gone up since 2008, our data show that there has been no improvement in financial liquidity between 2009 and 2011, except among families with more than $50,000 in savings and other liquid assets.”

Additional findings from the study, which can be read in its entirety HERE [PDF]:

*The proportion of families with no savings or other liquid assets rose to 23.4 percent in 2011, from 18.5 percent in 2009.

*About the same percentage of families in 2009 and 2011 had $30,000 or more in credit card and other non-collateralized debts (8.5 percent vs.10 percent) and about the same proportion (48.0 percent vs. 47.4 percent) had no such debt in both years.

“Even if they’re not underwater with their mortgages, [some families] are struggling to save money and reduce their debts,” says Stafford.

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