NEW YORK (CNNMoney.com) – Americans' net worth grew between 2001 and 2004, but not nearly as strongly as it did between 1998 and 2001, according to the Federal Reserve's triennial Survey of Consumer Finances released Thursday.

The big reason: while household assets increased, debts – particularly mortgage debt -- rose considerably more.

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By The Numbers American households, '01 - '04 • Wages: Down 6.2% • Net worth: Up 1.5%

Net worth: Median net worth rose 1.5 percent, to $93,100. The median is the point at which half of all households have a higher net worth and half have a lower net worth.

By contrast, between 1998 and 2001, the median net worth increased 10.3 percent.

The increase in net worth in the latest survey was due mostly to an increase in home ownership and an increase in housing prices.

Income: A decline in wages also helped account for the slow growth in net worth.

While the median income rose 1.6 percent, to $43,200, after adjusting for inflation, median wages fell 6.2 percent. Wages make up the largest part of family income.

Despite lower interest rates between 2001 and 2004, families spent more of their incomes paying off their debt.

The growth in income was the slowest since the Fed's 1992 survey, when median income actually fell.6.7 percent, to $35,100, between 1989 and 1992.

Savings: The percent of families who said they'd saved in the preceding year fell 3.1 percentage points, to 56.1 percent.

Similar to past surveys, 7 percent of families said their spending usually outpaces their income; 16.1 percent said they spend about what they make; 36.1 percent said they save income left over at the end of the year; and 40.8 percent said they save regularly.

Assets: The percentage of families who owned assets rose 1.2 percentage points to 97.9 percent.

The median value of all assets combined rose 10.3 percent to $172,900.

The survey breaks down assets into two categories: financial assets such as stocks and bonds, and non-financial assets such as homes.

The median value of financial assets fell 22.8 percent to $23,000.

Meanwhile, the median value of non-financial assets rose 22.2 percent to $147,800. (See correction below.)

Debt: The share of families with debt rose 1.3 percentage points to 76.4 percent.

Among families with debt of any kind -- including mortgages, other loans and credit cards -- the median level rose 33.9 percent to $55,300, far greater than the 9.5 percent increase seen between 1998 and 2001.

The median level of mortgage debt increased 27.3 percent to $95,000.

Stock ownership: The percentage of families investing in stocks, directly or indirectly through mutual funds, fell 3.3 percentage points, to 48.6 percent.

It's the first time the Fed has measured a decline in stock ownership, which had been on the rise since 1989, when the Fed began its first consumer finance survey.

The median value of stock-related holdings also fell, by 33.8 percent to $24,300.

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Correction: An earlier version of this article incorrectly stated that the median value of non-financial assets rose to $172,900. CNNMoney.com regrets the error.