Each of the five largest investment banks took on greater risk leading up to the subprime crisis. This is summarized by their leverage ratio, which is the ratio of total debt to total equity. A higher ratio indicates more risk. From fiscal years 2003-2007, these firms significantly increased their leverage ratios. A ratio of 10-15 is more typical of a conservative bank. These firms had ratios closer to 30.
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Origin work by en:User:Farcaster; Chinese Translation by Zanhsieh