There are financial, political, social and economic factors that determine the value of one currency against the next. And they are all rising or falling relative to each other.

"Aside from factors such as interest rates and inflation, the exchange rate is one of the most important determinants of a country's relative level of economic health. Exchange rates play a vital role in a country's level of trade, which is critical to most every free market economy in the world. For this reason, exchange rates are among the most watched, analyzed and governmentally manipulated economic measures. But exchange rates matter on a smaller scale as well: they impact the real return of an investor's portfolio."

"Before we look at these forces, we should sketch out how exchange rate movements affect a nation's trading relationships with other nations. A higher currency makes a country's exports more expensive and imports cheaper in foreign markets; a lower currency makes a country's exports cheaper and its imports more expensive in foreign markets. A higher exchange rate can be expected to lower the country's balance of trade, while a lower exchange rate would increase it."

Differentials in Inflation "As a general rule, a country with a consistently lower inflation rate exhibits a rising currency value, as its purchasing power increases relative to other currencies. During the last half of the twentieth century, the countries with low inflation included Japan, Germany and Switzerland, while the U.S. and Canada achieved low inflation only later. Those countries with higher inflation typically see depreciation in their currency in relation to the currencies of their trading partners. This is also usually accompanied by higher interest rates." Inflation "The amount of inflation in the economy has a large effect on exchange rates with currencies.