Title: Fixed-Income Securities
1Fixed-Income Securities
- Timothy R. Mayes, Ph.D.
- FIN 3600 Chapter 9
2What is a Bond?
- A bond is a tradable instrument that represents a
debt owed to the owner by the issuer. Most
commonly, bonds pay interest periodically
(usually semiannually) and then return the
principal at maturity.
3A Bond Certificate
4Advantages of Bonds over Stocks
- Bonds, while a more conservative investment than
stocks, can offer certain investors some very
attractive features - Safety
- Reliable income
- Potential for capital gains
- Diversification (especially for an otherwise
all-equity portfolio) - Tax advantages
5Safety of Bonds
- The safety of bonds derives mainly from two
things - Bondholders are in line ahead of both preferred
and common stockholders for payment. Thus, if a
firm falls on hard times, it must first pay its
bondholders while stockholders may see dividends
cut. - In the event that a company skips a payment or
violates covenants of the indenture, the
creditors may force it into bankruptcy to protect
the value of their investment. Stockholders have
no such right.
6Reliability of Income
- Most bonds are fixed-income securities. As
such, they promise a fixed set of interest
payments and the return of the principal at
maturity. - Investors can count on receiving their interest
payments in full and on time, except in the event
of severe financial distress. Common
stockholders can never be sure of the exact
amount (and sometimes the exact timing) of
dividends. - Bonds that are callable (most corporates and some
Treasuries issued before 1985) do not offer as
much reliability, though it is still far better
than stocks. As interest rates decline, the
probability of a call increases.
7Potential for Capital Gains
- Investors who do not hold a bond to maturity may
enjoy capital gains or suffer capital losses - When interest rates fall, bond prices rise. Thus
an investor who buys when rates are high, and
sells after rates fall will earn a capital gain.
The rate decrease may be due to general market
conditions or improvement in the companys
creditworthiness. - When interest rates rise, bond prices fall. Thus
an investor who buys when rates are low, and
sells after rates rise will suffer a capital
loss. The rate increase may be due to general
market conditions or a decrease in the companys
creditworthiness. - All other things being equal, as the bond moves
through time to maturity, the price must move
towards its face value. Thus, bonds purchased at
a discount will rise in price, and those
purchased at a premium will decline in price.
8Diversification
- Bonds, when added to an equity portfolio, can
lower risk while lowering returns slightly
(depending on the percentage of the portfolio
allocated to bonds). - While bond prices may be quite volatile, due to
the stability of the income that they provide
bond total returns tend to have low correlation
with stock returns. - The following slide shows the effect of adding
bonds to a stock portfolio.
9Diversification (cont.)
- The table below shows stock (SP 500) and bond
(VBIIX) returns from 1994 to 2000. Note that as
we increase exposure to bonds the return drops,
but not as quickly as the risk (standard
deviation).
10Tax Advantages of Bonds
- Some bonds are tax-advantaged
- Municipal bond income is free from federal income
taxes, and state income taxes in the state in
which they were issued. - Income from U.S. Treasury issues are free from
state and local income taxes. - Income from Savings Bonds (Series EE and I) is
free from state and local income taxes, and
federal income taxes on I Bonds may be deferred
for up to 30 years. Federal taxation may be
completely or partially eliminates when used for
education. - Note that the above tax benefits are for income
(interest payments) only. Any capital gains are
fully taxable at the local, state, and federal
levels.
11Basic Bond Valuation
- The intrinsic value of a bond, like stocks, is
the present value of its future cash flows. - Bonds, however, have much more predictable cash
flows and a finite life. - The cash flows promised by a bond are
- A series of (usually) constant interest payments
- The return of the face value of the bond at
maturity
12Basic Bond Valuation (cont.)
- The value of a bond is determined by four
variables - The Coupon Rate This is the promised annual
rate of interest. It is normally fixed at
issuance for the life of the bond. To determine
the annual interest payment, multiply the coupon
rate by the face value of the bond. Interest is
normally paid semiannually, and the semiannual
payment is one-half the annual total payment. - The Face Value This is nominally the amount of
the loan to the issuer. It is to be paid back at
maturity. - Term to Maturity This is the remaining life of
the bond, and is determined by todays date and
the maturity date. Do not confuse this with the
original maturity which was the life of the
bond at issuance. - Yield to Maturity This is the rate of return
that will be earned on the bond if it is
purchased at the current market price, held to
maturity, and if all of the remaining coupons are
reinvested at this same rate. This is the IRR of
the bond.
13Basic Bond Valuation Example
- Suppose that you are interested in purchasing a
3-year bond with a 10 semiannual coupon rate and
a face value of 1,000. If your required return
is 7, what is the intrinsic value of this bond? - Here is a timeline showing the cash flows
14Basic Bond Valuation Example (cont.)
- Note that the cash flows of the bond consist of
- An annuity, the interest payments, paid every six
months. This is calculated as - A lump sum which is the return of the face value
of the bond at the end of its life. This payment
is made at the same time as the last interest
payment.
15Basic Bond Valuation Example (cont.)
- We can find the intrinsic value of these cash
flows by finding the present value of the
interest payments and then adding the present
value of the face value - Note that the first term is the present value of
an annuity, and the second is the present value
of a lump sum - Do the math, and youll find that the bond is
worth 1,079.93. Note that this value must
decline until it reaches 1,000 at maturity.
16Bond Valuation Notes
- A few things of note with regard to the example
- The interest is paid semiannually, so we first
calculated the annual interest and the divided it
by two. If interest was paid, say, quarterly, we
would have divided the annual amount by four. - Similarly, we must convert the number of years to
maturity (3) into the total number of periods
(6). - Finally, we also must adjust your annual required
return (7) to a semiannual return (3.5). - These three variables must always be stated on a
per period basis. - Nearly all bonds (in the U.S.) pay interest more
often than annually. Most often this is
semiannually, but it could also be quarterly or
monthly.
17Valuing Bonds Between Coupon Dates
- The bond valuation formula just presented has one
major flaw It only works on a coupon date. - Since coupon dates (interest payment dates)
usually only occur twice per year, chances are (
99.45) youll buy (or sell) a bond between
coupon dates. - In this case, we must deal with accrued interest,
and the increase in the bond value since the last
coupon date.
18Valuing Bonds Between Coupon Dates (cont.)
- Imagine that we are halfway between coupon dates.
We know how to value the bond as of the previous
(or next even) coupon date, but what about
accrued interest? - Accrued interest is assumed to be earned equally
throughout the period, so that if we bought the
bond today, wed have to pay the seller one-half
of the periods interest. - Bonds are generally quoted flat, that is,
without the accrued interest. So, the total
price youll pay is the quoted price plus the
accrued interest (unless the bond is in default,
in which case you do not pay accrued interest,
but you will receive the interest if it is ever
paid).
19Valuing Bonds Between Coupon Dates (cont.)
- The procedure for determining the quoted price of
the bonds is - Value the bond as of the last payment date.
- Take that value forward to the current point in
time. This is the total price that you will
actually pay. - To get the quoted price, subtract the accrued
interest. - We can also start by valuing the bond as of the
next coupon date, and then discount that value
for the fraction of the period remaining.
20Valuing Bonds Between Coupon Dates (cont.)
- Lets return to our original example (3 years,
semiannual payments of 50, and a required return
of 7 per year). - As of period 0 (today), the bond is worth
1,079.93. As of next period (with only 5
remaining payments) the bond will be worth
1,067.73. Note that - So, if we take the period zero value forward one
period, you will get the value of the bond at the
next period including the interest earned over
the period.
P1
P0
Interest earned
21Valuing Bonds Between Coupon Dates (cont.)
- Now, suppose that only half of the period has
gone by. If we use the same logic, the total
price of the bond (including accrued interest)
is - Now, to get the quoted price we merely subtract
the accrued interest - If you bought the bond, youd get quoted
1,073.66 but youd also have to pay 25 in
accrued interest for a total of 1,098.66.
22Bond Return Measures
- There are three ways in which the expected return
of the bond is reported - Current Yield (CY)
- Yield to Maturity (YTM)
- Yield to Call (YTC)
- The current yield is simple, but inaccurate. The
yield to maturity (or yield to call) is much more
representative of the return you will receive,
but suffers from a problem of its own.
23The Current Yield
- The current yield on a bond is simply the annual
interest payment divided by its current price. - For our example bond, the current yield is
- Note that the current yield is ignoring the
capital loss that you will suffer over the
remaining life of the bond (it must sell for
1,000 at maturity), so it overstates the
expected return for bonds selling at a premium.
For discount bonds, the expected return is
understated.
24The Yield to Maturity
- The yield to maturity gives the exact return that
you will actually earn under the following
conditions - You purchase the bond at todays price
- You hold the bond to maturity
- You reinvest all interest payments at the same
YTM - The last condition is the most difficult to
achieve with interest rates changing all the
time. So, YTM is just an estimate of your actual
return. - However, the YTM does take into account the
increase or decrease in the price of the bond
(capital gain or loss) over the life of the bond.
25The Yield to Maturity (cont.)
- Suppose that we didnt know that our required
return was 7 per year, but we did know that the
current bond price was 1079.93. - We could solve for the yield implied by that
price (i.e., the YTM). - Unfortunately, there is no closed-form solution
to the bond valuation equation, so we need to use
a trial and error algorithm to find the yield.
26The Yield to Maturity (cont.)
- Here is the bond valuation equation, slightly
restated to make the point - Note that I have replaced the bonds intrinsic
value (VB) with its price (PB), and its required
return (kd) with its yield (YTM). - Our problem now is to solve for that YTM given
the price.
27The Yield to Maturity (cont.)
- To find the YTM, we first make a guess at the
yield. Say that we choose 10. That gives us a
price of 1,000 which is lower than the actual
price. To get the price to go up, we must lower
our estimated yield. - Suppose we now try 5. The price now is
1,137.70 which is too high. We need to try a
higher estimated yield. - Now, we know that the YTM must be between 5 and
10, so lets split the difference and try
7.5. We get 1,066.06. Close, but not close
enough. - We now know the YTM is between 5 and 7.5, so
choose 5.75. We get 1,115.59. We now know the
answer is between 5.75 and 7.5. - Next, try 6.625. We get 1,090.48.
- And so on. Keep splitting the difference until
you arrive at the correct price. The yield that
achieves this is the YTM. - This is the type of process that your calculator
goes through when solving for the YTM (the i
key). Eventually, you will find that the actual
yield is 7.
28The Yield to Call
- The yield to call (YTC) is exactly the same as
the YTM, except that it assumes that the bond
will be called at the next call date. - The only differences from calculating the YTM
are - We need to change the number of periods until
maturity to the number of periods until it can be
called. - If a call premium is to be received, we must
add that premium to the face value of the bond.
29Risks of Bonds
- Bonds are generally less risky than stocks, but
they do suffer from several types of risk - Credit risk Risk of default. (See ratings on
next slide) - Price risk Risk of unexpected changes in rates,
causing a capital loss. - Reinvestment risk Risk that rates will fall and
you will reinvest at a lower rate. - Purchasing power risk Risk that inflation will
be higher than expected. - Call risk Risk that the bond will be called
because of lower rates. - Liquidity risk The risk that you will not be
able to sell the bond at a price near its full
value. - Foreign exchange risk Risk that a foreign
currency will decline in value, causing a decline
in the value of your interest payments and
principal.
30Bond Ratings
- Credit risk is the most important source of risk
for owners of bonds. As a result, various rating
agencies (SP, Moodys, Fitch, and Dominion Bond)
assign grades to indicate the credit quality of
various bond issues. These ratings are similar
to those provided for insurance companies by A.M.
Best. - As you should guess, yields on lower rated bonds
will be higher (more risk) than those on higher
rated bonds (less risk). - Bond ratings are a lot like grades The agencies
give As, Bs, Cs, and Ds with various schemes
to differentiate within the category (i.e., AAA
is better than AA).
31Bond Ratings (cont.)
32Bond Ratings (cont.)
- Note from this and the next slide, that there is
virtually no risk of default within 1 year, and
very little over longer periods, if you invest in
investment grade securities. - One you go below investment grade, however, the
risk of default rises dramatically.
33Bond Ratings (cont.)
34Bond Ratings (cont.)
35Corp. Bond Spreads Over Treasuries
- This table demonstrates that bond yields (spreads
over equivalent Treasuries) increase as credit
ratings decline. - Note also that the spreads widen as maturity
increases.
36Malkiels Bond Pricing Theorems
- In 1961, Burton Malkiel published a paper where
he proved five important bond pricing theorems - Bond prices move inversely to interest rates
- Longer maturity bonds respond more strongly to a
given change in interest rates - Price sensitivity increases with maturity at a
decreasing rate - Lower coupon bonds respond more strongly to a
given change in interest rates - Price changes are greater when rates fall than
they are when rates rise (asymmetry in price
changes)
37Duration
- Two of Malkiels theorems relate directly to bond
price volatility. - He showed that the longer the term to maturity,
the greater the change in price, but the coupon
rate also affects volatility (lower coupons
more volatility). - These same observations led Frederick Macaulay to
look for a better measure of volatility than just
the term to maturity. In 1938, he discovered
duration which combines maturity and coupon rate
to describe a bonds price volatility.
38Duration (cont.)
- Suppose that we have two bonds, identical except
for their term to maturity. Both bonds have
coupon rates of 10 paid annually (for
simplicity), and face values of 1,000. Your
required return is 10. Bond 1 has 5 years to
maturity while Bond 2 has 10 years to maturity. - The price of each bond is 1,000 (do the math).
- Now, if your required return drops to 8, which
bond will increase the most in value? - Bond 1 will be worth 1,079.85, and Bond 2 will
be worth 1,134.20 - Bond 2 wins because of its longer maturity (see
Malkiels theorem 2). - Note that had rates risen instead, then Bond 1
would lose less than Bond 2 so Bond 1 would be
favored.
39Duration (cont.)
- Now, suppose that our bonds both have 5 years to
maturity, but Bond 3 has a coupon rate of 7 and
Bond 4 has a coupon rate of 10. - With your required return at 10, Bond 3 is worth
886.28, and Bond 4 is worth 1,000 (do the
math). - If your required return drops to 8, which bond
will increase more in value? - Bond 3 will be worth 960.73 (an increase of
8.40), and Bond 4 will be worth 1,079.85 (an
increase of 7.99). - So Bond 3, with the lower coupon rate wins (see
Malkiels theorem 4).
40Duration (cont.)
- Finally, what if Bond 5 has a maturity of 5 years
and a 5 coupon, while Bond 6 has a maturity of
10 years and a 10 coupon? - Now we have a conflict. Bond 5 has a lower
coupon rate, but Bond 6 has a longer maturity.
How do we know which one will change more in
price when rates drop to 8? - First, note that at 10 Bond 5 is worth 810.46
and Bond 6 is worth 1,000. - At 8, Bond 5 is worth 880.22 (an 8.6
increase), and Bond 6 is worth 1,134.20 (and
increase of 13.42). - Bond 6 wins because it has a longer duration.
41Calculating Duration
- Duration is a measure of the effective life of
the bond. It is a weighted-average term to
maturity where the weights are the present values
of the cash flows - Where DMac is the Macaulay duration, CFt is the
cash flow in period t, and P0 is the current
price of the bond.
42Calculating Duration (cont.)
- Lets calculate the durations of Bond 5 and Bond
6 from the last example, using a 10 required
return - So, Bond 5 has a duration of 4.49 years. Similar
calculations will show that Bond 6 has a duration
of 6.76 years. - The longer duration is the reason that Bond 6
outperformed Bond 5 when rates fell to 8.
43Properties of Duration
- A longer term to maturity increases duration, all
other things being equal. However, duration
increases with term to maturity at a decreasing
rate. - For coupon-bearing bonds, duration is always less
than term to maturity. For zero-coupon bonds it
is exactly the same as term to maturity. - Lower coupon rates lead to longer durations, all
other things being equal. - Higher yields lead to shorter durations.
- When calculating duration for semiannual bonds,
the resulting duration will be in semiannual
periods. You must adjust this back to annual by
dividing by 2.
44The Use of Macaulay Duration
- Macaulay duration is a very useful tool in bond
portfolio management - When interest rates are expected to move, a
portfolio manager should change the duration of
the portfolio to take maximum advantage (or limit
damage) of the change. - Also, by using an immunization strategy, we can
eliminate both price risk and reinvestment risk
to guarantee a certain amount of funds will be
available to meet needs on a certain future date.
45Modified Duration
- Macaulay duration is a poor predictor of the
percentage change in a bonds price when its
yield changes. We can improve this approximation
by calculating the modified duration - Bond 5 has a modified duration of
46Modified Duration (cont.)
- Bond 6 has a modified duration of 6.14 years.
- Note that we can calculate the approximate
percentage change in price of a bond as - So, when rates drop by 2, we would find that
Bond 5 should change by approximately
47Modified Duration (cont.)
- Lets compare the approximations to the actual
changes - Bond 5 Actual 8.6, Approximate 8.16
- Bond 6 Actual 13.42, Approximate 12.29
- Why were the approximations so far off?
- Mainly because of the huge (200bp) decline in
rates. Duration is technically only correct for
very small changes in rates. - The relationship between price and yield is
non-linear, but duration measures linear changes. - If we used only a small change in rates (say,
0.1 or 1bp) we would be much closer. - If we took account of the non-linear relationship
(known as convexity which is beyond the scope of
this class) we would get closer still. - Note though, that the modified duration correctly
tells us that Bond 6 will increase in value
significantly more than Bond 5. This is really
the important result.