Answer:
currency fluctuation
Explanation:
In foreign exchange, currency fluctuation refers to the changes in value of a currency. Normally free floating currencies (whose value is determined by the market) will appreciate or depreciate against other currencies. When a currency appreciates, it gains value against other currency, for example in 2008 1 euro was worth $1.60. When a currency depreciates, it loses value against other currencies, e.g. in 2016 the euro was worth around $1.