BOX 5.1 The Mundell–Fleming model under capital controls
In this book we assume that capital moves unhindered
across borders. This describes the current situation
quite well in industrial and many other
countries. But there are still some countries,
mostly in the developing world, that do not permit
free movements of capital in and out. In
Tanzania, for example, citizens need to submit
proof of an import contract and obtain a permit if
they want to acquire foreign currency. The purchase
or sale of currency is usually not permitted
for financial investments. As a consequence the
capital account cannot really respond to interest
rate differentials. In algebraic terms k = 0 in equation
(4.5). What does that do to the FE curve? This
is best seen after solving the general FE curve,
equation (4.7), for Y to obtain
Letting k = 0 to signal that capital is not permitted
to respond to changes in interest rates, the interest
differential drops out of the equation and
equation (1) simplifies to
FE curve under capital controls
This equation restates the current account equilibrium
(equation (4.3)) we derived in Chapter 4.
Obviously, when there are no capital flows and,
thus, CP = 0, the foreign exchange market can
only be in equilibrium if the current account is in
equilibrium: CA = EX - IM = 0.
The FE curve under strict capital controls is a
vertical line, just as is the CA = 0 line in Chapter 4,
the position of which is determined by the real
exchange rate and world income. The reasons for
this are exactly the same as those given for why
the position of the CA = 0 line depends on R and
YWorld. See Figure 4.4 and the explanations given
there. The general macroeconomic equilibrium is
as depicted in Figure 1.
■ Can you explain why FE moves right when the
real exchange rate depreciates?
■ Can this country stimulate income by raising
government spending when the exchange rate
is fixed?