Abstract

The Optimal Level of Current Account Credit

For the event that the time path of the balance on a current account can be forecast (at least approximately), the article shows when and to what extent a higher yield is attainable by means of withdrawal of an additional amount and putting it to some other fairly long-term use, and also by taking up a correspondingly higher credit on current account in periods of especially high money requirements. Following ventilation of the relevant changes in interest and commission rates and, based on the foregoing, deliberations regarding the anticipatable change in yield which is dependent on the geometry of the curve for the balance on the account, a graphic-mathematical method applicable to any time path of the balance is developed for determining yield changes. Then follows an analytical determination of the optimal level of current account credit for exemplary special cases: 1. uniformly declining balance, 2. periodical in-payment at the beginning and uniform outpayments during the period, 3. periodical withdrawal at the beginning and uniform in-payments during the period, and 4. sinusoidal path of the balance. A concrete numerical example shows that the optimum credit level and the additional yield attainable if that level is realized are quite substantial. The article closes with a brief treatment of possible variations and other applications of the method