Question

What changes and supply and demand cause currency to become weaker or depreciate?

Answer 1

When investors expect a country’s currency to strengthen in the future, they demand and buy more currency and cause it to appreciate immediately. The appreciation of the currency can lead other investors to believe that future appreciation is likely—and thus lead to even further appreciation. Similarly, a fear that a currency might weaken quickly leads to an actual weakening of the currency, which often reinforces the belief that the currency is going to weaken further. Thus, beliefs about the future path of exchange rates can be self-reinforcing, at least for a time, and a large share of the trading in foreign exchange markets involves dealers trying to outguess each other on what direction exchange rates will move next.