Investments in real estate have whittled away at the net worth of the average American family.

The inflation-adjusted net worth for the typical household was $87,992 in 2003. Ten years later, it had dropped 36 percent to $56,335, according to a studyfinanced by the Russell Sage Foundation, The New York Times reported.

During the same period, the net worth of wealthy households increased 14 percent.

Among other things, the findings reveal how vulnerable the average American has become to the swings in the housing market, according to Bloomberg Businessweek.

Starting around 2001, American families put an increasing amount of their wealth in housing and took on more debt. This came at the expense of other kinds of investments, such as non-housing wealth, which hasn't returned to its 2001 peak.

The median real estate asset value (including primary residence and other property holdings) increased 38 percent with the housing bubble. The median value is the middle point between a set of numbers.

At the same time, the median value of financial assets such as checking accounts, 401(k) plans, stocks, and bonds dropped 9 percent from 2001 to 2007- a time when the Standard & Poor's 500 stock index was up more than 20 percent. The value of nonfinancial assets - cars, jewelry, business ownership - also fell by 18 percent, leaving the average household overexposed to real estate, Bloomberg Businessweek said.