Key Concepts and Summary

Key Concepts and Summary

In the extreme short run, ranging from a few minutes to a few weeks, exchange rates are influenced by speculators who are trying to invest in currencies that will grow stronger, and to sell currencies that will grow weaker. Such speculation can create a self-fulfilling prophecy, at least for a time, where an expected appreciation leads to a stronger currency and vice versa. In the relatively short run, exchange rate markets are influenced by differences in rates of return. Countries with relatively high real rates of return (for example, high interest rates) will tend to experience stronger currencies as they attract money from abroad, while countries with relatively low rates of return will tend to experience weaker exchange rates as investors convert to other currencies.

In the medium run of a few months or a few years, exchange rate markets are influenced by inflation rates. Countries with relatively high inflation will tend to experience less demand for their currency than countries with lower inflation, and thus currency depreciation. Over long periods of many years, exchange rates tend to adjust toward the purchasing power parity (PPP) rate, which is the exchange rate such that the prices of internationally tradable goods in different countries, when converted at the PPP exchange rate to a common currency, are similar in all economies.

Glossary

arbitrage

the process of buying a good and selling goods across borders to take advantage of international price differences

purchasing power parity (PPP)

the exchange rate that equalizes the prices of internationally traded goods across countries