# Modern Money Mechanics/Bank Reserves—How They Change

Money has been defined as the sum of transaction accounts in depository institutions, and currency and travelers checks in the hands of the public. Currency is something almost everyone uses every day. Therefore, when most people think of money, they think of currency. Contrary to this popular impression, however, transaction deposits are the most significant part of the money stock. People keep enough currency on hand to effect small face-to-face transactions, but they write checks to cover most large expenditures. Most businesses probably hold even smaller amounts of currency in relation to their total transactions than do individuals.
Since the most important component of money is transaction deposits, and since these deposits must be supported by reserves, the central bank's influence over money hinges on its control over the total amount of reserves and the conditions under which banks can obtain them.
The preceding illustrations of the expansion and contraction processes have demonstrated how the central bank, by purchasing and selling government securities, can deliberately change aggregate bank reserves in order to affect deposits. But open market operations are only one of a number of kinds of transactions or developments that cause changes in reserves. Some changes originate from actions taken by the public, by the Treasury Department, by the banks, or by foreign and international institutions. Other changes arise from the service functions and operating needs of the Reserve Banks themselves.
The various factors that provide and absorb bank reserve balances, together with symbols indicating the effects of these developments, are listed on the opposite page. This tabulaton also indicates the nature of the balancing entries on the Federal Reserve's books. (To the extent that the impact is absorbed by changes in banks' vault cash, the Federal Reserve's books are unaffected.)

##### Independent Factors Versus Policy Action

It is apparent that bank reserves are affected in several ways that are independent of the control of the central bank. Most of these "independent" elements are changing more or less continually. Sometimes their effects may last only a day or two before being reversed automatically. This happens, for instance, when bad weather slows up the check collection process, giving rise to an automatic increase in Federal Reserve credit in the form of "float." Other influences, such as changes in the public's currency holdings, may persist for longer periods of time.
Still other variations in bank reserves result solely from the mechanics of institutional arrangements among the Treasury, the Federal Reserve Banks, and the depository institutions. The Treasury, for example, keeps part of its operating cash balance on deposit with banks. But virtually all disbursements are made from its balance in the Reserve Banks. As is shown later, any buildup in balances at the Reserve Banks prior to expenditure by the Treasury causes a dollar-for-dollar drain on bank reserves.
In contrast to these independent elements that affect reserves are the policy actions taken by the Federal Reserve System. The way System open market purchases and sales of securities affect reserves has already been described. In addition, there are two other ways in which the System can affect bank reserves and potential deposit volume directly; first, through loans to depository institutions, and second, through changes in reserve requirement percentages. A change in the required reserve ratio, of course, does not alter the dollar volume of reserves directly but does change the amount of deposits that a given amount of reserves can support.
Any change in reserves, regardless of its origin, has the same potential to affect deposits. Therefore, in order to achieve the net reserve effects consistent with its monetary policy objectives, the Federal Reserve System continuously must take account of what the independent factors are doing to reserves and then, using its policy tools, offset or supplement them as the situation may require.
By far the largest number and amount of the System's gross open market transactions are undertaken to offset drains from or additions to bank reserves from non-Federal Reserve sources that might otherwise cause abrupt changes in credit availability. In addition, Federal Reserve purchases and/or sales of securities are made to provide the reserves needed to support the rate of money growth consistent with monetary policy objectives.
In this section of the booklet, several kinds of transactions that can have important week-to-week effects on bank reserves are traced in detail. Other factors that normally have only a small influence are described briefly on page 35.

##### Factors Changing Reserve Balances—Independent and Policy Actions

| | FEDERAL RESERVE BANKS | FEDERAL RESERVE BANKS | FEDERAL RESERVE BANKS |
| | Assets | Liabilities | |
| | | Reserve Balances | Other |
| Public Actions ||||
| Increase in currency holdings............... | | - | + |
| Decrease in currency holdings............. | | + | - |
| Treasury, bank, and foreign actions ||||
| Increase in Treasury deposits in F.R. Banks...... | | - | + |
| Decrease in Treasury deposits in F.R. Banks..... | | + | - |
| Gold purchases (inflow) or increase in official valuation.. | | + | - |
| Gold sales (outflows)....................... | | - | + |
| Increase in SDR certificates issued.................... | | + | - |
| Decrease in SDR certificates issued.................. | | - | + |
| Increase in Treasury currency outstanding................... | | + | - |
| Decrease in Treasury currency outstanding................... | | - | + |
| Increase in Treasury cash holdings......... | | - | + |
| Decrease in Treasury cash holdings......... | | + | - |
| Increase in service-related balances/adjustments..... | | - | + |
| Decrease in service-related balances/adjustments....... | | + | - |
| Increase in foreign and other deposits in F.R. Banks........ | | - | + |
| Decrease in foreign and other deposits in F.R. Banks.... | | + | - |
| Federal Reserve actions ||||
| Purchases of securities.................................... | + | + | |
| Sales of securities................................... | - | - | |
| Loans to depository institutions........... | + | + | |
| Repayment of loans to depository institutions......... | - | - | |
| Increase in Federal Reserve float.................. | + | + | |
| Decrease in Federal Reserve float...................... | - | - | |
| Increase in assets denominated in foreign currency ...... | + | + | |
| Decrease in assets denominated in foreign currency ...... | - | - | |
| Increase in other assets..................................... | + | + | |
| Decrease in other assets..................................... | - | - | |
| Increase in other liabilities..................................... | | - | + |
| Decrease in other liabilities.................................. | | + | - |
| Increase in capital accounts............................. | | - | + |
| Decrease in capital accounts.......................... | | + | - |
| Increase in reserve requirements................. | | - | |
| Decrease in reserve requirements................. | | + | |
*: These factors represent assets and liabilities of the Treasury. Changes in them typically affect reserve balances through a related change in the Federal Reserve Banks' liability "Treasury deposits."
**: Included in "Other Federal Reserve accounts" as described on page 35.
***: Effect on excess reserves. Total reserves are unchanged. Note: To the extent that reserve changes are in the form of vault cash, Federal Reserve accounts are not affected.