From 2004-07, the top five U.S. investment banks each significantly increased their financial leverage (see diagram), which increased their vulnerability to a financial shock. These five institutions reported over $4.1 trillion in debt for fiscal year 2007, about 30% of USA nominal GDP for 2007. Lehman Brothers was liquidated, Bear Stearns and Merrill Lynch were sold at fire-sale prices, and Goldman Sachs and Morgan Stanley became commercial banks, subjecting themselves to more stringent regulation. With the exception of Lehman, these companies required or received government support.
