International Economics Prof. S. K. Mathur Department of Humanities and Social Science Indian Institute of Technology, Kanpur
International Economics Prof. S. K. Mathur Department of Humanities and Social Science Indian Institute of Technology, Kanpur
International Economics Prof. S. K. Mathur Department of Humanities and Social Science Indian Institute of Technology, Kanpur
Prof. S. K. Mathur
Department of Humanities and Social Science
Indian Institute of Technology, Kanpur
Lecture No. # 03
Good afternoon. In todays lecture, we will talk about how expenditures affect the
national income and the current account balance of the countries. So, I will write down
the equations which will tell us how expenditures of a country are related to the national
income of a country, and how expenditures affect the current account balance of the
country. And then, we will introduce interdependence in the model. And then at the end,
we will try to figure out, whether a deficit or a surplus, which is generated by the
changes in expenditures or they sustained or are they negated in the interdependent
model. So, the equations are the following.
(Refer Slide Time: 01:22)
policy induced expenditures or the autonomous changes in net exports, it tends to have
an impact on the incomes. This one upon s plus m is the open economy multiplier, where
in s is the marginal propensity to save, and m is the marginal propensity to import of the
country.
The second equation tells us that if there is change in the autonomous private
expenditures or policy induced expenditures. It tends to deteriorate your current account
balance reason being that, if you increase the autonomous private expenditures and
policy induced expenditures, they tends to have an impact on the incomes as the incomes
rises the imports go up. So, there is a deterioration in the current account balance, but if
there is a switch in expenditures in favors of say the domestic goods from foreign to
domestic goods d N a goes up and it leads to an improvement in the current account
balance. So, if there is an increase in d N a, it will have an impact on the incomes, but, it
will also improve the current account balance.
Now, you can see from here that if there is an improvement in the current account
balance it has an impact on the incomes. And we are also saying that it improves the
current account balance. So, whatever is the impact on the incomes and through incomes,
there is a change in the imports. It is still not able to wipe out the surplus which is
created, by the shift of expenditures from foreign to domestic goods. So, this is the point
that needs to be understood, and what we need to probe further is that, if we bring in
interdependence in the model and if there is a switch in expenditure from foreign to
domestic goods, Will it still lead to an increase in the current account balance? Or will
there be still be balance of payment surplus?
So, think of this in a manner that, say for example, we introduce another country, we
introduce another country which is say Japan and this is US or your country is India. And
you introduce the Indias major trading partner now as china. Now think of what
happens? If there is a change in the autonomous private expenditures in India .what we
will see is that it not only improves the incomes here, but it also improves the incomes in
the other countries.
But on the other hand, it deteriorates our current account balance, because the as the
incomes goes up the imports go up. But an as a result, this current account balance is
comes to be negative. Now when you have interdependent model, when you increase
So, if you have to bring in, the interdependent model. You need to have some changes in
this term d N a ,d N a earlier was d X a minus d M a plus M star d Y star .Where you had
assumed that the incomes of the foreign country are constant and m star is the marginal
propensity to import. Now in this interdependent economy, the change is that, you define
d N 1 A to be d X 1 a minus d M 1 a .And d N 2 a to be d X 2 a minus d M 2 a and d N 2
a is minus d N 1 a.
So, the equations would become d Y 1 upon 1 plus M 1 d A1 A plus d A 1 g plus d N 1
a. And you would have M 2 d Y 2 divided by s 1 plus M 1. Now see the how this term as
emerged? Because, now d N 1 A is d X 1 A minus d 1 d N 1 A and this is M 2 d y 2. So,
if you take it out of the bracket, here out of the parenthesis, you will get M 2 d Y 2
divided by s 1 plus m 1. Similarly you can define d Y 2 to be equal to 1 upon S 2 plus M
2 d A 2 a plus d A 2 g minus d N 1 a plus M 1 d Y 1 divided by S 2 plus M 2. Please
recall that your d A 2 a or d A is d I a minus d S a .And d A g which reflects the fiscal
and the monitory policy of the government is d minus s r minus I R d R.
So, the change is now this change in the autonomous export term, autonomous change is
in the net exports. Now it is a little curtailed one, it is d X 1 a minus d N 1 a and d N 2 a
is d X 2 a minus d m 2 a which minus d N 1 a. So, now, you have these two countries we
are studying the interdependence model. You have two equations in two unknowns;
these have to be solved to get the values of d Y 2 and d Y 2.
So, I will spend some time on the board and then solve these simultaneous equations.
And, see what finally, comes out? What impacts the changes in the incomes? And you
will find that, it is not only your expenditures that is your countrys expenditures. But
their countrys expenditures also having an impact on your incomes. And then once we
have these figures, we will also get a figure for or current account balance.
(Refer Slide Time: 13:03)
Similarly, if you solve for d Y 2, you can always get a value .You can always get the
incomes of the second country.
(No audio 19:18 to 20:05).
Now, look at the changes, which can happen in the incomes of your trading partner? The
expenditures which are done there? It tends to have an impact on the incomes through
the Keynesian multiplier. But your expenditures, your countrys expenditures also tend
to promote incomes in the other countries. And any improvement in the net exports, say
for example, if there is a switch in expenditure from foreign to domestic goods, which
improves your net exports. It tends to deteriorate the net exports there; it tends to have a
negative impact on the incomes.
But, what you should be able to understand from these two things? Is that if d N 1 a
increases, it tends to increase the incomes in your country. And it leads to a decline in
incomes in the other country. When there is a decline in incomes in the other country, it
leads to a decline in imports. And when there is a decline in imports, it leads to a decline
in exports. And yet, it is not able to wipe out the current account surplus that is created
right at the beginning. To further explain the last point that I just mentioned, I need to get
a figure for the change in net exports, which is d X..
(Refer Slide Time: 23:41)
exports go up. So, there is a marginal improvement in the current account balance and
therefore, the net result is that there is still underline current account deficit in your
balance of payments. So, even when you bring in interdependence, it is not able to wipe
out the current account deficit which is created by giving a shock to the system that is
increasing the expenditures in the economy.
So, in todays lecture, we see that even if you have interdependent model, it is not able to
adjust fully to the shocks which are given initially in the model. So, that is where we will
end today in the next lecture .We will talk about how to remove deficit and surplus in the
balance of payments , thank you.