The left-hand side of Eq. (15.3) is the percentage interest
cost savings that borrowers would enjoy by borrowing
in foreign currency. The right-hand side, on the other
hand, is the percentage loss they would take in the currency
markets by having to repay their debt with more
expensive foreign currency.
By precisely the same logic, if the CIP held, Eq. (15.1)
would imply that borrowers who sought to take advantage
of relatively low foreign currency interest rates by
borrowing abroad and using forward contracts to hedge
their currency risk would be disappointed as well. In this
case, they would find that the forward premium that
they had to pay to purchase foreign currency in the forward
market would exactly offset the interest savings
they enjoyed. As above, this relationship is readily apparent
by dividing both sides of Eq. (15.1) by (1þRi
* ), ,t
subtracting 1, and rearranging terms to get