If a country is an attractive place for foreigners to invest their funds, then that country will have a relatively high exchange rate. If it's an unattractive place, it will have a relatively low exchange rate. Those are the fundamentals that determine the exchange rate in a floating exchange rate system.
Milton FriedmanFundamentally, there are only two ways of coordinating the economic activities of millions. One is central direction involving the use of coercion - the technique of the army and of the modern totalitarian state. The other is voluntary cooperation of individuals - the technique of the marketplace.
Milton Friedman