You may have encountered two other words to denote movements in exchange
rates: “revaluations” and “devaluations.” These two terms are used when countries operate
under fixed exchange rates—a system in which two or more countries maintain
a constant exchange rate between their currencies. Under such a system, increases
in the exchange rate—which are infrequent by definition—are called revaluations
(rather than appreciations). Decreases in the exchange rate are called devaluations
(rather than depreciations).