126 INTERNATIONAL FINANCIAL MANAGEMENT
influencing exchange rates. In such situations, the PPP theory cannot give a correct
estimate of exchange rates.
• The PPP theory holds only in the long run. In other words, long run changes in
exchange rates are in line with long run differences in inflation rates.
It should be noted that PPP holds more during periods of hyperinflation, when the money
supply is usually out of control. With excess supply of money in the economy and expecta-
tions of a continuing rise in price levels, money turns over swiftly. That is, the increasing
velocity of money (the average number of times each unit of money changes hands during
a given period) will bid up the price level and drive down the exchange value of th ...