Flows of Capital and Goods
In the first macroeconomics SparkNote on
measuring the economy, we learned the
identity Y = C + I + G + NX to describe the output of an economy.
In this equation, Y is the
nominal output, C is money spent on consumption, I is money
spent on investment, G is money spent by the government,
and NX is net exports or exports less imports. The sum
of these costs is the total amount of both income
and output in
a country.
To understand how capital and goods flow in and out of
countries, we should keep the Y = C + I + G + NX
identity in mind. NX is of particular interest. NX is
defined as the total amount of exports less the total
amount of imports. NX is positive if a
country exports more than it imports, negative if a country
imports more than it exports, and zero if exports and
imports are equal.
Let's work through each of these examples in turn. First we'll examine the
simplest case, in which exports and imports
are equal. In this example, there are two countries,
Country A and Country B. If Country A exports 1 million
dollars worth of coconuts to Country B and imports 1
million dollars worth of bananas from Country B, then the
NX for both countries is equal to zero since exports
equal imports. In this case, goods are traded for goods
and at the end of the term, the trade balance is equal.
When countries import less than they export or import
more than they export, the situation becomes significantly more
complicated. Now let's examine the case when a country
imports more than it exports. If Country A exports 0.5
million dollars worth of coconuts to Country B and imports
1 million dollars worth of bananas from Country B, then
Country A has a negative trade balance, called a trade
deficit. In this case, Country A owes Country B money for
the imported bananas beyond the 0.5 million dollars worth
of exported coconuts. If this is a short-term debt,
nothing of consequence would occur since Country A has the
ability to export more coconuts quickly to make up for the
difference.
If the debt is long term, however, Country A
must somehow repay Country B for the imported bananas. The
easiest way to think of this exchange is to imagine Country
A giving Country B interest in the future coconuts produced
by Country A. To repay the debt that
Country A owes to Country B, Country B becomes invested in
Country A. Any amount of exports that exceeds
the total amount of imports results in foreign investment.
The opposite occurs when exports exceed imports as the
exporting country becomes a foreign investor in the
importing country.
This leads us to another important
international trade identity: NX = NFI where NX is net
exports or exports less imports and NFI is net foreign
investment. Simply put, the difference between what a
country exports and imports is equal to
the amount of foreign investment. The trade balance can
remain fairly even if a country
imports more than it exports--it must
make up the difference through foreign investment.
If net exports remain equal to net foreign investment,
a few tendencies arise:
- countries with few
imports and many exports will tend to have significant
foreign investment
- countries with few exports and many imports will also
tend to have significant foreign investment
- countries with exports equal to imports will tend to
have little investment in foreign countries and little
foreign investment
Understanding the identity NX = NFI and the means by which
capital and goods flow between countries helps to clarify
the workings of international trade.