THE CHANGES

Under current rules, banks must hold back at least 4 percent of their balance sheet to cover their risks. This mandatory reserve -- known as tier 1 capital -- would rise to 4.5 percent by 2013 under the new rules and reach 6 percent in 2019.

In addition, banks would be required to keep an emergency reserve known as a "conservation buffer" of 2.5 percent. In total, the amount of rock-solid reserves each bank is expected to have by the end of the decade will be 8.5 percent of its balance sheet.