DETERMINATION OF EXCHANGE RATES

There is no generally accepted theory or model to determine exchange rates. However, there are certain approaches which provide a general frame-work for analysis of exchange rates which are discussed below:

(a) Balance of Payments: If payments by a country for its imports of goods and services and invisibles are out of step with its receipts for exports of goods and services and invisible, two possibilities arise. One foreign currency payments exceed receipts and there is a deficit. This puts the home currency of the country under downward pressure against foreign currencies. Two, there is a surplus and there is an upward pressure on the home currency. In the former case, the home currency tends to depreciate, and in the later to appreciate, against foreign currencies.

(b) Demand and supply: The demand for a foreign currency to pay for imports, etc, and the supply of a foreign currency by way of receipts on account of exports, etc. vary at various rates of exchange. The rate which equilibrates the demand and supply should be the rate of exchange.

(c) Purchasing power parity: This theory maintains that free international trade equalises prices of tradable goods in different countries. So, a product will sell for the same price in common currency in all countries. Different rates of changes in prices i.e. different inflation rates must eventually induce off-setting changes in exchange rates in order to restore approximate price equality. Mathematically, the rate (or the expected rate) of change of the exchange rate should equal the rate (or the expected rate) of change of the inflation rate. Evidence shows that there do exist disparities between changes in observed exchange rates and those in inflation rates in the short-run. But, the theory should hold in the long-run.

(d) Interest rate: Interest rates are often highly related with inflation rates, and interest rate differentials between countries may be the result of inflation rate differentials. Therefore, interest rate differentials are also used as an important determinant of exchange rates.

Interest rates in a country are determined, under free market conditions, by supply of and demand for money. Funds flow across countries in search of opportunities for higher returns. These flows between any two countries cause opposite changes in demand of and supply for their respective currencies. According to the theory of International Fisher Effect, the exchange rate of a currency with higher interest rate will depreciate to offset the interest rate advantage achieved by foreign investments till an equilibrium is achieved.

Investments abroad have to be converted into home currency on maturity. Exchange rate may have changed in the meanwhile. An investor may make a forward sale of funds to be rapatriated on maturity. The process of investing abroad for higher returns and making a forward sale of the proceeds is known as covered interest arbitrage. An investment abroad will be undertaken if the return from interest rate differential exceeds the forward margin (difference between the forward and spot exchange rates). In general terms, the forward rate of the foreign currency will contain a discount (premium) if its interest rate is higher (lower) that that of the home currency. Covered interest arbitrages will go on fill the market forces realign the forward margins with the interest rate differentials.

(e) Relative Income Levels: If income level in a country raises and that in her trading partner remains unchanged, the demand by the former for the goods of the later may increase. That is, the former would need more units of currency of the later, while their supply remains unchanged. This would put upward pressure on the exchange rate of the later. There can be different configurations of the relative income levels and of corresponding exchange rates.

(f) Market expectations: Like other financial markets, foreign exchange markets react to any news that may have an effect on exchange rates in future. Expected developments regarding polity, economy etc. of a country are used to figure out how exchange rates would move. These peeps into future impinge on the present as well as the future spot rates.