Factors influencing Foreign Exchange Rates:
Macroeconomic Factors: Relative inflation, balance of payments, foreign exchange reserves, economic growth, government spending, money supply growth, and interest rate policy.
Political Factors: Exchange rate control, election year or leadership change.
Random Factors: Unexpected and/or unpredicted events, fear of uncertainty, etc.
Many countries attempt to maintain a lower value for their currency in order to encourage exports.