Currency peg

A fixed exchange rate, sometimes called a pegged exchange rate, is a type of exchange rate regime where a currency's value is fixed against either the value of another single currency, to a basket of other currencies, or to another measure of value, such as gold.

There are benefits and risks to using a fixed exchange rate. A fixed exchange rate is typically used in order to stabilize the value of a currency by directly fixing its value in a predetermined ratio to a different, more stable or more internationally prevalent currency (or currencies), to which the value is pegged. In doing so, the exchange rate between the currency and its peg does not change based on market conditions, the way floating currencies do. This makes trade and investments between the two currency areas easier and more predictable, and is especially useful for small economies, economies which borrow primarily in foreign currency, and in which external trade forms a large part of their GDP.

A fixed exchange-rate system can also be used as a means to control the behavior of a currency, such as by limiting rates of inflation. However, in doing so, the pegged currency is then controlled by its reference value. As such, when the reference value rises or falls, it then follows that the value(s) of any currencies pegged to it will also rise and fall in relation to other currencies and commodities with which the pegged currency can be traded. In other words, a pegged currency is dependent on its reference value to dictate how its current worth is defined at any given time. In addition, according to the Mundell–Fleming model, with perfect capital mobility, a fixed exchange rate prevents a government from using domestic monetary policy in order to achieve macroeconomic stability.

In a fixed exchange-rate system, a country’s central bank typically uses an open market mechanism and is committed at all times to buy and/or sell its currency at a fixed price in order to maintain its pegged ratio and, hence, the stable value of its currency in relation to the reference to which it is pegged. The central bank provides the assets and/or the foreign currency or currencies which are needed in order to finance any payments imbalances.

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