Open Economy Macro: The transmission mechanism through the real exchange rate.

Open Economy Macro:The transmission mechanism

through the real exchange rate

2

The Transmission Mechanism in Open Economy Macro

We saw that changes in domestic saving and investment, or changes in world interest rates, or domestic risk premiums would affect net exports.

How does that happen?

Through the adjustment of the real exchange rate.

Let see how.

Financial Globalization

0

20

40

60

80

100

120

140

160

180

1980 1985 1990 1995 2000 2005 2010

US foreign assets/ GDPForeigners US assets/ GDP

Ass

ets

as %

of U

S G

DP

fig_finglob_2013

4

Summary on Exchange Rates

I will only sketch basics in class. Refer to notes and text.• Foreign-exchange rates are the relative prices of

different national monies or currencies.• Convention: exchange rates = amount of foreign

currency per unit of domestic currency (e.g., Japanese Yen: 100 yen to $.)

• Notation: e = nominal exchange rate; R = Real exchange rate

• Appreciation = rise in e or R; depreciation = fall

5

Exchange rates

Foreign-exchange rates are the relative prices of different national monies or currencies.

Convention in Econ 122 and Mankiw: Nominal exchange rate • exchange rates = amount of foreign currency per unit of

domestic currency.• Think Japanese Yen: 100 yen to $.

Notation: e = nominal exchange rate; R = Real e.r.Appreciation = rise in e or R; depreciation = fallReal exchange rate, R [Mankiw uses ε)

R = nominal exchange rate corrected for relative prices

R = e × (p d / p f )= p d / (p f / e)

= domestic prices/foreign prices in a common currency

6

Exchange rates

Foreign-exchange rates are the relative prices of different national monies or currencies.

Convention in Econ 122 and Mankiw: Nominal exchange rate • exchange rates = amount of foreign currency per

unit of domestic currency.• Think Japanese Yen: 100 yen to $.

7

Terminology

For market-determined exchange rates:• An appreciation of a currency is when the value of

the currency rises– e or R rises

• A depreciation of a currency is when the value of the currency falls– e or R falls

For fixed exchange rates:• Price set by government is the “parity.”• A revaluation is an increase in the official parity.• A devaluation is a decrease in the parity.

8

Index of US nominal exchange rate (e)

Appreciation

Depreciation

This is the “broad index” of major countries.

9

Summary on Exchange Rates

I will only sketch basics in class. Refer to notes and text.• Foreign-exchange rates are the relative prices of

different national monies or currencies.• Convention: exchange rates = amount of foreign

currency per unit of domestic currency (e.g., Japanese Yen: 100 yen to $.)

• Notation: e = nominal exchange rate; R = Real exchange rate

• Appreciation = rise in e or R; depreciation = fall• Real exchange rate = nominal exchange rate

corrected for relative pricesR = e × (p d / p f )

= p d / (p f / e)

= domestic prices/foreign prices in a common currency

10

Real exchange rates

Real exchange rate, R [Mankiw uses ε) R = nominal exchange rate corrected for relative

prices

R = e × (p d / p f )= p d / (p f / e)

= domestic prices/foreign prices in a common currency

Note: If you calculate the rate of growth of R, you get

Example of car exchange rate: 100 Yen/$; Toyota = 2,000,000Y; Ford = $20,000; R = 100 * 20000/2000000 = 1 Toyota/Ford

rate of real rate of nominal domestic foreign

appreciation appreciation inflation rate inflation rate

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Big Mac Real Exchange Rate

R = p d / (p f / e)

Example of Big Mac*Price in Beijing: 13 YuanPrice in New York: $3.73Real exchange rate: $3.73/(Y13/6.7) = $3.73/($1.97) = 1.89

People use this to argue that Yuan is “overvalued.”Anything wrong with this argument?

* http://www.economist.com/node/16646178?story_id=16646178

Real exchange rate of $ relative to major currencies (R)Appreciation

Depreciation

Dollar bubble with high interest rates

Flight to $safety

Dot.com stockbubble

We saw last time that changes in the domestic S-I balance led to changes in NX (the trade balance).

We need next to understand the macroeconomic mechanism by which this occurs.

We will see that this operates through changes in the real exchange rate, which leads to changes in the relative prices of foreign and domestic goods.

Now to the Macroeconomic Equilibrium

Saving-Investment Balance in Open Economy

NX(R) = Spriv + Sg – I(rw)

Net domestic saving = net foreign investment= lending abroad = ΔNFA

Recall S does not depend upon r (but unimportant for our analysis)

Small open economy with mobile capital means rd = rw

The only new relationship is NX(R):– Real deprecation (R ↓) lowers the price of exports in foreign

markets and raises import P in domestic markets.– This raises exports and lowers imports; raising NX.– Hence NX’(R) < 0

Putting this with the S-I curves, we can see how real exchange rate is determined.

15

Net exports and the real exchange rate

Real exchange rate (R)

NX(R)

NX0

R*

NX*

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Savings-investment and the determination of the real exchange rate:

NX(R) = Sn-I(rw)

R

NX(R)

0

R*

NX*

Sn-I(rw)

E*

Have two behavioral relationships: (1) NX and (2) net savings.

R and NX are determined as the equilibrium of

these two functions.

S-I, NX

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Why does fiscal tightening lead to a lower trade deficit?

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Fiscal policy:G ↓ →net S ↑ → R ↓ →NX ↑

R

NX(R)

S-I, NX0NX*

(S-I(rw))*

E**

(S-I(rw))**

NX**

E*

Fiscal tightening

Impact of protectionism

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Protectionism

R

NX(R)

S-I, NX0NX*=NX**

(S-I(rw))

R*

R**

NX(R)’

Counterintuitive:Trade measures lead to real appreciation, not to change in trade balance!

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Now analyze large open economy

Large Open Economy: - Country large enough to affect world financial markets- Domestic assets imperfect substitutes for foreign assets.- Because imperfect substitutes, domestic r differs from foreign r (rd ≠ rw)

AnalysisGoods markets:(1) NX(R) = Sn – I(rd) Financial market equilibrium:

CF = net financial investment abroad = - financial surplus(2) CF = CF(rd, rw). In analysis, we suppress rw

Notes that capital flows in if domestic interest rates rise CF’(rd) < 0.

Domestic interest rate (rd)

CF0CF*

CF(rd)

rd

Equation (2)

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Now analyze large open economy

Large Open Economy: - Country large enough to affect world financial markets- Domestic assets imperfect substitutes for foreign assets.- Because imperfect substitutes, domestic r differs from foreign r (rd ≠ rw)

AnalysisGoods markets:(1) NX(R) = Sn – I(rd) Financial market equilibrium:

CF = net financial investment abroad = - financial surplus(2) CF = CF(rd, rw). In analysis, we suppress rw

Notes that capital flows in if domestic interest rates rise CF’(rd) < 0.

Equilibrium comes when (1) and (2) equilibrate the balance of payments:(3) NX(R) = CF(rd) = Sn – I(rd) In our diagrams below, we use (3): (4) I(rd) + CF(rd) = Sn = Spriv + Sg

Domestic interest rate (rd)

CF

CF(rd)

rd

S, I,CF

Sn

I(rd)+CF(rd)

Real exchange rate, R

0NX

NX(R)

R*

NX*

rd*

0

CF*

Bernanke’s surprising theory of why the US deficit is so high

“I will argue that over the past decade a combination of diverse forces has created a significant increase in the global supply of saving--a global saving glut--which helps to explain both the increase in the U.S. current account deficit and the relatively low level of long-term real interest rates in the world today.” (Bernanke, 2005)

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Global savings glut: Global effect

S, I

Real interest rate (r)

Id (r)

I*

r*

Sworld **Sworld *

r**

I**

Domestic interest rate (rd)

CF

CF(rd)

rd

S, I,CF

S

I+CF

R

0NX

NX(R)

R*

NX*

rd*

0

Bernanke’s “world savings glut”

- Current situation is one in which rest of world has savings glut (particularly China, Japan, and oil exporting countries accumulating $ reserves).

- This increases inflows to US.- This is leading to low world and

US real interest rates - and to the large US trade deficit.

Here are the basic data (pre-crisis)

-.06

-.05

-.04

-.03

-.02

-.01

.00

.01

2

4

6

8

10

12

14

16

80 82 84 86 88 90 92 94 96 98 00 02 04

Net exports/ GDP10-year T-bond rate

T-bond rate (----> )

NX/ GDP ( <---- )

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That’s it for classical open-economy macro

Next session: To business-cycles and the Keynesian model.

Key insight: Financial dog wags trade tail

Dog of trade

Tail of finance!