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Effect on the Money Supply of Turning Cash into a Checkable Deposit at First Street BankWhen Silas deposits $1,000 (which had been stashed under his bed) into a checkable bank account, there is initially no effect on the money supply: currency in circulation falls by $1,000, but checkable bank deposits rise by $1,000. The corresponding entries on the bank’s T-account, depicted in panel (a), show deposits initially rising by $1,000 and the bank’s reserves initially rising by $1,000. In the second stage, depicted in panel (b), the bank holds 10% of Silas’s deposit ($100) as reserves and lends out the rest ($900) to Mary. As a result, its reserves fall by $900 and its loans increase by $900. Its liabilities, including Silas’s $1,000 deposit, are unchanged. The money supply, the sum of checkable bank deposits and currency in circulation, has now increased by $900—the $900 now held by Mary.