Exchange rates are determined by the supply and demand for a particular currency. When there is a high demand for a currency, its value will increase, and the exchange rate will go up. Conversely, when there is a low demand for a currency, its value will decrease, and the exchange rate will go down.

There are several factors that can influence the supply and demand for a currency, including:

1. Interest rates: Higher interest rates can attract foreign investment and increase the demand for a currency, leading to an appreciation in value. Conversely, lower interest rates may discourage foreign investment and lead to a depreciation in value.
2. Inflation: Higher inflation can lead to a depreciation in the value of a currency, as it reduces the purchasing power of the currency. Conversely, lower inflation can lead to an appreciation in the value of a currency.
3. Political and economic stability: A stable political and economic environment can increase the demand for a currency, leading to an appreciation in value. Conversely, political and economic instability can lead to a depreciation in value.
4. Trade balances: A country with a trade surplus (exports exceed imports) may see an appreciation in the value of its currency, as it generates foreign exchange through exports. Conversely, a country with a trade deficit (imports exceed exports) may see a depreciation in the value of its currency.
5. Speculation: Speculative activity can also affect the supply and demand for a currency, as traders buy and sell currencies based on their expectations of future price movements.

Overall, exchange rates are influenced by a wide range of factors, and they can fluctuate significantly in response to changing market conditions.