sentences:  The United States passed the Dodd–Frank Act in July 2010 to help strengthen regulation of the financial system in the wake of the subprime mortgage crisis that began in 2007.Dodd–Frank requires banks to reduce their risk taking, by requiring greater financial cushions (i.e., lower leverage ratios or higher capital ratios), among other steps.Banks are required to maintain a ratio of high-quality, easily sold assets, in the event of financial difficulty either at the bank or in the financial system.