One such liability is the outstanding amount of Federal Reserve notes in circulation—that is, paper money—which has doubled over the past decade to a volume of more than $ trillion, growing at a rate that generally reflects the pace of expansion of economic activity in nominal terms.
Other nonreserve liabilities have also grown since the crisis, including the Treasury Department’s account at the Fed, known as the Treasury’s General Account. Recent growth in such items means that the longer-run size of the Fed’s balance sheet will be noticeably larger than before the crisis regardless of the volume of reserve balances that might ultimately prevail.