§ 4. #Time deposits.# Time deposits are funds to the credit of customers which, by agreement, are to be left for some specified minimum time or on condition that the bank may require notice in advance of the depositor's intention to withdraw them. The notice that may be required is usually thirty to ninety days; but only in times of general financial crises or of runs on particular banks is this requirement enforced. A sufficient deterrent to irregular withdrawal of funds is usually found in the loss of interest if deposits are withdrawn at other than stated times. The bank's right to require notice makes prudent the investment of a much larger proportion of its deposits and for a longer time; it reduces the proportion of deposits needed for reserves, and yet reduces the danger of a "run" upon the bank in time of financial distress. These are reasons why banks can and usually do pay interest on time deposits (at from 2 to 4 per cent), as until more recently they rarely did on demand deposits[4]. From the standpoint of the depositor a time deposit is, by its very nature, an investment and not a demand credit available for current monetary uses. Only that portion of a person's capital that for some more or less considerable period is not likely to be needed for other purposes ought to be put into time deposits. A bank, however, is generally a much safer place in which to keep a fund of purchasing power for the future than is the strongest private treasure box. Receiving time deposits is the one essential function of savings banks, but this function is increasingly performed by other banks[5]. Sometimes time deposits are cared for by a separate department and kept separate from the general business of a commercial bank. § 5. #Demand deposits#. Demand deposits are those payable on demand, the demand in practice being by means of personal checks requesting the bank to pay to (or on the order of) a specified person, or to pay to bearer. A customer's bank account consisting of demand deposits is called a checking account. Since the turn of the century it has become increasingly the practice to pay a low rate of interest (about 2 per cent) on current balances, oftener to large depositors. Banks attract demand deposits mainly by the convenience and economy which they offer to their customers in the guarding of funds from theft and fire and in saving the time, trouble, and expense of carrying money for making payments. A deposit in a bank is to the depositor for most purposes "just as good" as money in the pocket and for many purposes is even better. Thus the banks have become the custodians of a large proportion of the money (or funds) needed for current use by individuals and business corporations.