chapter 7 the risk and term structure of interest …jneri/econ330/files/lecture...term structure of...
TRANSCRIPT
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Chapter Seven
Chapter 6 – Part 2
Term Structure
of Interest Rates
Term Structure of Interest Rates • Why do bonds with the same default rate and
tax status but different maturity dates have different yields?
– Long-term bonds are like a composite of a series of short-term bonds.
– Their yield depends on what people expect to happen in the future.
• How do we think about future interest rates?
Term Structure of Interest Rates • The relationship among bonds with the same
risk characteristics but different maturities is called the term structure of interest rates.
• Comparing 3-month and 10-year Treasury yields we can see: 1. Interest rates of different maturities tend to move
together.
2. Yields on short-term bonds are more volatile than yields on long-term bonds.
3. Long-term yields tend to be higher than short-term yields – but NOT always
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Term Structure of Interest Rates
Yield Curve Yield Curve: A plot of the term structure, with the yield to
maturity on the vertical axis and the time to maturity on the
horizontal axis.
https://www.treasury.gov/resource-center/data-chart-center/Pages/index.aspx
http://www.stockcharts.com/freecharts/yieldcurve.php
Three Term Structure Theories 1. Pure Expectations Theory/Hypothesis - explains
the first two facts but not the third
2. Segmented Markets Theory - explains fact three
3. Liquidity Premium Theory combines the two theories to explain all three facts
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The Expectations Hypothesis • Assumes an investor will be indifferent between
holding a 2-year bond or a series of two 1-year bonds.
– bonds of different maturities are perfect substitutes for each other.
• The expectations hypothesis implies that the current 2-year interest rate should equal the average of current 1-year rate and the 1-year interest rate one year in the future.
The Expectations Hypothesis • If current interest rate is 5 percent and future
interest rate is expected to be 7 percent, then the current two-year interest rate will be (5+7)/2 = 6%.
• When interest rates are expected to rise, long-term interest rate will be higher than short-term interest rates.
– The yield curve will slope up.
• This also means: – If interest rates are expected to fall, the yield curve will
slope down.
– If expected to stay the same, the yield curve will be flat.
The Expectations Hypothesis
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The Expectations Hypothesis • If bonds of different maturities are perfect
substitutes for each other, then we can construct investment strategies that must have the same yields.
• Options:
1. Invest in a 2-year bond and hold it to maturity
• i2t is interest rate on a 2-year bond bought today, t.
• One dollar yields (1 + i2t)(1 + i2t) two years later.
The Expectations Hypothesis
2. Invest in two 1-year bonds, one today and one when the first matures.
– One-year bond today has interest i1t.
– One-year bond purchased in year 2 has interest ie1t+1, where e is expected.
– One dollar invested today returns
(1 + i1t)(1 + ie1t+1).
The Expectations Hypothesis
• The expectations hypothesis tells us investors will be indifferent between the two options.
• This means they must have the same return:
(1 + i2t)(1 + i2t) = (1 + i1t)(1 + ie1t+1)
• We can now write the two-year interest rate as the average of the current and future expected one-year interest rates:
i2t i1t i1t1
e
2
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The Expectations Hypothesis
• Returning to our example: • i1t = 5%
• ie1t+1 = 7%
• The interest rate on a 1-year bond is 5% and the interest rate on a 2-year bond is 6%.
%0.62
%7%5
2
1112
e
ttt
iii
A Note on Averages
• Geometric average of and =
• Arithmetic average =
• The arithmetic average is an approximation.
1ti 1 1ti
1/ 2
1 1 1((1 )(1 )) 1t ti i
1 1 1
2
t ti i
Quiz: 2 year investment horizon – 2 options
• Option/strategy 1:
• Invest $1,000 for 2-years at 8%:
• Ending Balance = $1,166.40
• Option/strategy 2:
• Invest $1,000 1-year at 6% and expect 9% one year later:
• Ending Balance = $1,155.40
• Which is the better strategy and why?
• What happens to S and D?
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The Expectations Hypothesis
A 3-year Bond:
The Expectations Hypothesis
• An N-year Bond:
• We can generalize this: a bond with n years to maturity is the average of n expected future one-year interest rates:
int i1t i1t1
e i1t2e ... i1tn1
e
n
Expectations Hypothesis - Arithmetic Average
In words: The interest rate on a bond with n years to maturity at time t is the average of the n expected future one-year rates.
Numerical example:
One-year interest rate over the next five years 5%, 6%, 7%, 8% and 9%:
Interest rate on a two-year bond:
(5% + 6%)/2 = 5.5%
Interest rate for a five-year bond:
(5% + 6% + 7% + 8% + 9%)/5 = 7%
Interest rate for one, two, three, four and five-year bonds are:
5%, 5.5%, 6%, 6.5% and 7%.
n
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This is the only interest rate that is
known at time t
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Expectations Hypothesis
Another example: One-year interest rate over the next five years 7%, 6%, 5%, 4% and 3%:
Interest rate on a two-year bond:
(7% + 6%)/2 = 6.5%
Interest rate for a five-year bond:
(7% + 6% + 5% + 4% + 3%)/5 = 5%
Interest rate for one, two, three, four and five-year bonds:
7%, 6.5%, 6%, 5.5% and 5%.
n
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Side Note
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Recall the Fisher Equation: i = r + πe
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This says long term interest rates equal the average
real interest rate and the average rate of inflation
expected over the life of the bond.
From the Fisher Equation: i = r + πe
• Holding r constant:
• If inflation is expected to rise in the future, expected
one-year interest rates will rise and the yield curve will
slope upward.
• If inflation is expected to fall in the future, expected
one-year interest rates will fall and the yield curve will
slope downward.
• If inflation is expected to remain the same in the future,
expected one-year interest rates will remain the same
and the yield curve will be flat.
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Expectations Theory: i = r + πe
i
2
1
2
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In general:
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From the formula for the yield on a 2-year bond:
From the formula for the yield on a 3-year bond:
Using the Expectations Theory to Solve for Expected
1-year (forward) Interest Rates
i
3
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In general:
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Example: Calculate iet+2
i3t = 5% and i2t = 4%; iet+2 = 3(5%) – 2(4%) = 7%
Using the Expectations Theory to Solve for Expected
1-year (forward) Interest Rates
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The Expectations Hypothesis
Does this hypothesis explain the three observations we started with?
1. Interest rates of different maturities will move together. – Yes. Long term interest rates are averages of
expected future short-term interest rates.
2. Yields on short-term bonds will be more volatile than yields on long-term bonds. – Yes. Long-term rates are averages of short-term
rates, so changing one short-term rate has little effect on the long term rate.
The Expectations Hypothesis
3. This hypothesis cannot explain why long-term yields are normally higher than short term yields.
– It implies that the yield curve slopes upward only when interest rates are expected to rise.
– This hypothesis would suggest that interest rates are normally expected to rise.
Segmented Market Theory
• Bonds of different maturities are not perfect
substitutes for each other.
• Key assumptions:
• Investors have specific preferences about the maturity
or term of a security.
• Investors do not stray from their preferred maturity.
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Segmented Markets Hypothesis
• The slope of the yield curve is explained by different demand and supply conditions for bonds of different maturities.
• If the yield curve slopes up, it does so because the demand for short term bonds is relatively greater than the demand for long term bonds.
• Short term bonds have a higher price and a lower yield as a result of the relatively greater demand. So the yield curve slopes upward.
Segmented Markets Hypothesis
Price Price
0 0
S S
P2s
P1s P1
l
P2l
D1s
D2s
D1l
D2l
Quantity of Short-term Bonds Quantity of Long-term Bonds
Upward Sloping Yield Curve
Segmented Markets Hypothesis
• The segmented markets hypothesis explains
why….
• Yield curves typically slope upward.
• On average, investors prefer bonds with shorter
maturities that have less interest rate risk.
• Therefore, the demand for short term bonds is
relatively greater than the demand for long-term
bonds
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Segmented Markets Hypothesis
• But, the segmented markets hypothesis does not
explain why…
• Interest rates on different maturities move
together.
• The segmented markets hypothesis assumes that
short and long markets are completely segmented.
The Liquidity Premium Theory • In order to explain all 3 facts we need to extend
the expectations hypothesis to include risk.
• Bondholders face both inflation and interest-rate risk.
– The longer the term of the bond, the greater both types of risk.
The Liquidity Premium Theory Inflation Risk
• Real return is what matters and computing real return from nominal return requires a forecast of expected future inflation.
– The further into the future we look, the greater the uncertainty.
– A bond’s inflation risk increases with its time to maturity.
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The Liquidity Premium Theory
Interest-rate risk
• arises from the mismatch between the investor’s investment horizon and a bond’s time to maturity.
– If a bondholder plans to sell a bond prior to maturity, changes in the interest rate generate capital gains or losses.
– The longer the term of the bond, the greater the price change for a given change in interest rates and the larger the potential for capital losses.
The Liquidity Premium Theory
• Investors require compensation for the increase in risk they take for buying longer term bonds.
• We can think about bond yields as having two parts:
– One that is risk free - explained by the expectations hypothesis.
– One that is a risk premium - explained by inflation and interest-rate risk.
The Liquidity Premium Theory • Together this forms the liquidity premium theory
of the term structure of interest rates.
• We can add the risk premium (rpn) to our previous equation to get:
• The liquidity premium theory explains all three of our observations about the term structure of interest rates.
n
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Numerical Example
Term in years (n)
1 2 3 4 5
One year interest rate
expectations 5% 6% 7% 8% 9%
Liquidity premium 0% 0.25% 0.5% 0.75% 1.0%
Pure expectations
predicted n-year bond
interest rates
5% 5.5% 6% 6.5% 7%
Actual n-year bond
interest rates,
accounting for liquidity
preference
5% 5.75% 6.5% 7.25% 8%
5% 6%
2
5% 6% 7%
3
5 6 7 8%
4
5 6 7 8 9%
5
Relationship Between the Liquidity Premium and
Expectations Theories
(if short term interest rates are
expected to remain constant)
Information Content of Interest Rates:
Term Structure
• When the yield curve slopes down,
it is called inverted
• An inverted yield curve
is a very valuable forecasting tool
• It signals an economic downturn
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Market
Predictions
of Future
Short
Rates
The Information Content of Interest Rates
• Risk spreads provide one type of information, the term structure another.
• We can apply what we have just learned to recent U.S. economic history to show how forecasters use these tools.
Information in the Risk Structure of Interest Rates
• The immediate impact of a pending recession is to raise the risk premium on privately issued bonds.
– Note that an economic slowdown or recession does not affect the risk of holding government bonds.
– The impact of a recession on companies with high bond ratings is also usually quite small.
• The lower the initial grade of the bond, the more the default-risk premium rises as general economic conditions deteriorate.
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Information in the Risk Structure of Interest Rates
• Panel A of Figure 7.8 shows the annual GDP growth over four decades superimposed on shading that shows the dates of recessions.
– During shaded periods growth is negative.
• Panel B of figure 7.8 shows GDP growth against the spread between yields on Baa-rated bonds and U.S. Treasury bonds.
– risk spread rises during recessions.
• During financial crises, people take cover.
• They sell risky investments & buy safe ones.
• An increase in the demand for government bonds coupled with a decrease in the demand for virtually everything else is called a flight to quality.
– This leads to an increase in the risk spread.
• The 1998 Russian default on its bonds led to a serious flight to quality causing the financial markets to cease to function properly.
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Information in the Term Structure of Interest Rates
• Information on the term structure, particularly the slope of the yield curve - helps to forecast general economic conditions. – The yield curve usually slopes upward.
– On rare occasions, short-term interest rates exceed long-term yields leading to an inverted yield curve.
• This is a valuable forecasting tool because it predicts a general economic slowdown. – Indicates policy is tight because policymakers are
attempting to slow economic growth and inflation.
Information in the Term Structure of Interest Rates
• Figure 7.9 shows GDP growth and the slope of the yield curve, measured as the difference between the 10-year and 3 month yields: term spread.
• Panel A shows GDP growth together with the term spread at the same time.
• Panel B shows GDP growth in the current year against the slope of the yield curve one year earlier. – The two lines clearly move together.
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Information in the Term Structure of Interest Rates
• When the term spread falls, GDP growth tends to fall one year later.
• This shows that the yield curve is a valuable forecasting tool.