The Exchange Rate: Dollars for Yen or Yen for Dollars, Which Way is It?

Forex exchange-rate index is designed to measuremedia and it squares with the intuitive idea of
how, over time, movements in the dollar will affectappreciation or devaluation of the dollar. When Forex
U.S. imports and exports. And to do this well, Forexexchange as we have defined it goes up (e.g., from
index must also take account of any differences100 yen to 120 yen), the dollar buys more foreign
between the rate of inflation in the United Statescurrency - the dollar has appreciated. When Forex
and the rates of inflation in other countries. Supposeexchange rate goes down (e.g., from 100 yen to 90
that the rate of inflation were 10 percent a year inyen), the dollar buys less foreign currency - the dollar
the United States but only 3 percent a year inhas depreciated.
Germany. The buying power of the dollar in theUnfortunately, this approach is the inverse of the
United States is falling 7 percent a year faster thanconcept that international trade economists focus on
the buying power of the German mark.when they describe Forex foreign-exchange markets.
Now suppose that Forex exchange rate of the dollarThey define Forex exchange rate in terms of the
declined by 7 percent from one year to the nextprice of foreign exchange, so the yen to dollar
against the mark. Then German buyers would beexchange rate is the cost of purchasing one yen with
getting 7 percent more dollars for their marks; butdollars. If Forex exchange rate in our terms is equal
the decline in the exchange rate would be exactlyto 100 yen to the dollar, the inverse would be $0,01
undone by the greater increase in prices in the United(one cent) per yen. If the dollar appreciates, from
States than in Germany. The number of Mercedes100 yen to 120 yen to the dollar (dollar purchases
that it took to trade for one Boeing 757 would bemore yen), then Forex exchange rate, expressed as
the same in the two years. (At least, this would bethe cost of yen, declines in dollar terms, in this
true on average for many goods.) This means that,example dropping from $0,01 to $0,0083.
when a change in Forex exchange rate simplyThe appreciating dollar means that yen purchased in
compensates for differences in inflation rates, theforeign exchange Forex markets are now cheaper to
relative prices of U.S. imports (from Germany) andbuy with dollars, exactly the concept that trade
U.S. exports (to Germany) do not change.economists wish to show. But it also means that their
Readers let us notify: international Forex tradedefinition of the Forex dollar-exchange rate falls when
economists do it differently. One of the mostthe dollar appreciates! This is very confusing and so
confusing concepts in economics is the way in whichwe define Forex exchange rate as yen per dollar,
Forex rate of exchange between two currenciesrather than dollars per yen.
should be expressed. As we indicate in the article, weFor those who go on to further studies in
choose to express the rate as the number of unitsinternational economics, however you, you will find
of foreign currency that can be purchased with onethat the trade economists' definition usually appears in
dollar (e.g., let's say the yen is trading at 130 yen tointernational Forex articles and journals.
the dollar). This approach is commonly used in the