Following the financial crisis of the 2000's, many now view big banks as trustworthy, foolproof institutions. However, that may not be the case. A recent Harvard University study indicates that markets now see banks as much more likely now to lose half their market value than before the crisis. The study, conducted by Natasha Sarin and former Treasury Secretary Larry Summers, also indicated a decent decrease in the ratio of banks' market value to the value their books say they are worth.