Q. Show the Changes in the exchange rate?
Assume that United States is our home country and the current euro exchange rate in direct notation is SD = 1.5 (euro/USD). In indirect notation, SI = 0.667 (USD/euro). If euro becomes more costly in terms of the USD we say that USD has depreciated against the euro (lost in value). It means that SD has increased (to say SD = 1.6) and that SI has fallen (to 0.625). If euro becomes less expensive we say that USD has appreciated against the euro. In such a case, SD will fall and SI will increase. Obviously, when USD depreciates against the euro, euro appreciates against the USD.
Remember:
A foreign currency is more expensive Û domestic currency has depreciated
A foreign currency is less expensive Û domestic currency has appreciated
Also keep in mind that whenever a currency depreciates, S will increase if we use direct notation and decrease if we use indirect notation.
If a country has a fixed exchange rate (say against a particular currency), government or central bank may change this fixed exchange rate. Suppose that Hong Kong is our home country and that Hong Kong dollar (HKD) is fixed against USD at the exchange rate 7.8 HKD/USD (direct notation). If central bank in Hong Kong changes this exchange rate to say 8.2 HKD/USD it makes foreign currency more expensive and HKD cheaper. In this case we say that HKD has beendevalued. Though, if exchange rate is changed to say 8.6 HKD/USD we say that HKD has been revalued.