American wealth Net worth has risen for two straight quarters after shrinking last spring. Associated Press WASHINGTON -- Americans' wealth grew 3.8 percent in the final three months of 2010, boosted by gains in stock portfolios. Companies, meanwhile, added to their cash stockpiles, which reached their highest point in more than a half-century. Household net worth rose to $56.8 trillion in the October-December quarter, even though the value of real-estate holdings fell 1.6 percent, the Federal Reserve said Thursday. Last quarter's gain exceeded the 2.6 percent increase in net worth in the July-September period. So far this year, stocks have risen more than 3 percent. Further gains in wealth could lead Americans -- especially higher-income consumers -- to spend more, strengthening the economy. Net worth is the value of assets such as homes, checking accounts and investments, minus debts like mortgages and credit cards. It's now risen for two straight quarters after shrinking last spring.