Finance 3310

Lecture Notes

Lecture 6

I. Bond valuation

a) definition of terms

b) basic valuation model

c) yield to maturity

d) interest rate risk

e) miscellaneous


BONDS:

Definition of Terms

1. Bond - a long-term security which promises to make fixed interest payments and a principal payment at maturity. Also called:

debt security

fixed income security

2. Par value - the stated or face amount of bond (usually $1,000 or $5,000)

3. Maturity date - date on which par amount is repaid

4. Coupon interest rate - stated or promised annual rate of interest on the bond. Most bonds make semi-annual coupon payments. The coupon payment in this case is the coupon rate x par amount ÷ 2. The coupon rate simply defines the bond's cash flows.

i) 0 coupon bond - As the name implies, these bonds have no coupon payments. They are created by investment banks who take government bonds and split the principal and interest into separate securities. (P only and I only in WSJ)

ii) contrast w/ market rate or yield to maturity

iii) market rate usually = coupon rate at issue date

5. call provisions - give the issuer the right to buy back the bond at a predetermined price prior to maturity. When are issuers likely to 'buy back' a previously issued bond?

Next we want to look at bond valuation. This task is made easier by noting that the value of anything is simply the value today of that anything's future cash flows. Thus, the value of a bond is simply the present value of the bond's future cash flows.




Bond Valuation


A bond is just a stream of fixed cash flows

* principal or par or face amount

* interest payments

0 --------I------- I-------- I-------- I------- I-------- I------ I, P

|______|______|______|______|______|______|______|

where I = coupon payment (coupon rate x par amount) and P = par amount.

* The coupon interest payment is just an annuity

* The principal payment is a single cash flow.

* discount rate ==> Rd = investors' required return on the bond; same as market rate or yield on bond.

Thus, we find the present value of an annuity and the present value of a single cash flow, and then just add the two together. Later, we will do it all at once on the calculator.

Mathematically:

Bond Value =


T7.4 Ex 1: Assume interest is paid annually:

What is cost of bond if i = 100, n = 20, P = 1000 & Rd = 10%?

i) PV(annuity) 100, 20, 10% = 851.36

ii) PV of $1,000 20 yrs from now = 148.64

iii) cost = value = 851.36 + 148.64 = $1,000

This bond is said to be 'selling at par' or selling 'flat.'

T7.5 Ex 2: Same bond as above except that now Rd = 12%.

i) PV(annuity) 100,20,12% = 746.94

ii) PV of 1,000 20 yrs from now = 103.66

iii) cost = value = 746.94 + 103.66 = 850.60

This bond is selling at a discount ==> cost < par

Why?? The reason is, the bond is paying 10%, but the market demands 12%. Stated somewhat differently, this bond is priced to yield 12%. That is, if you pay 850.60 for the bond and rates do not change, you would earn 12%. (prove this: hold the bond for one year and then sell it, assuming rates remain at 12%. What is the rate of return on your investment?)


T7.6 Ex 3: Same bond as above except that now Rd = 8%.

i) PV(annuity) 100,20,8% = 981.81

ii) PV of 1,000 in 20 yrs = 214.55

iii) cost = value = 1,196.36

Here, cost > par ===> bond selling at premium

Why? The bond is paying 10% but market only demands 8%. This bond is 'priced to yield' 8%.

Instead of finding the present value of an annuity and adding to it the present value of a single cash flow, it turns out we can do this all at once on our calculator. Consider the first example above. We key into the calculator what we know (I, P, Rd & n) and solve for what we don't know (PV).

FV = P = 1,000

Pmt = I = 80

I = Rd = 10%

n = 20

PV = ? (value of bond)

Suppose that instead of annual coupons, the bonds have semi-annual coupons. Rework examples 1 through 3 assuming semi-annual coupons. (1,000; 849.53; 1,197.93)



Summary of key points


1. If market rate, Rd, = coupon rate, then cost = par . Bond is selling flat.

2. If market rate > coupon rate, then

==> cost < par

==> Bond is said to be selling at a discount

3. If market rate < coupon rate, then

==> cost > par

==> Bond is said to be selling at a premium

4. a) An increase in market rates ==> bond prices fall (T7.7)

b) A decrease in market rates ==> bond prices rise

Why are bond prices and interest rates inversely related? Very simply, because of the present value equation:

PV = CF/(1+R)n : As R increases, PV decreases

5. The market value approaches par over time.

Why? Because the bond pays the (promised) par amount at maturity.

bonds selling at a premium ==> mkt gets lower

bonds selling at a discount ==> mkt gets higher

The actual time path of bond prices could involve both discounts and premiums depending on the movement in market interest rates.


Zero coupon:

1. no interest payment

2. Par is future value

3. Sells at discount (why?) Also called 'deep discount' bonds

4. Cost is just PV of future par amount

Yield to Maturity (YTM)

The yield to maturity is:

1. The rate earned if bond is held to maturity.

2. The rate which discounts all future cash flows to their current value (price)

3. The 'market' rate for the bond in question

Given the current price of the bond and the bond's expected future cash flows (par & interest), what rate do you expect to earn on the bond if you buy it at its current price and hold it to maturity (and rates don't change again).

Technically:

price =

We know the price, I, and P and want to find the Rd that solves the above equation.

How do you find it?

a) trial and error

We know if the bond is selling at a discount ytm > coupon

And, if the bond is selling at a premium ytm < coupon

ex: Suppose the price of a bond which matures in 10 years with a coupon of 8% is 875.00. What is YTM??

1. Since selling at a discount, YTM > coupon

2. Try 10% PV(I) = 531.42 , PV(P) = 385.54 -----> Cost = 916.63

3. Try a higher rate; say 11%

PV(I) = 471.14 PV(P) = 352.18 ----> Cost = 823.22

4. Now, try something in between; say 10.5%

PV(I) = 481.18 PV(P) = 368.44 ----> Cost = 849.63

5. Repeat; rate is between 10 and 10.5%

b) Calculator

Again, key in what you know and solve for what you don't know. As an example, suppose the price of a 10% coupon (annual), 20 year maturity bond is $1,196.36. What is the YTM? (note: this is example 3 above)

FV = 1,000

PV = (1,196.36)

n = 20

Pmt = 100 (10% x 1,000)

i = YTM = ? (8%)

Suppose the bond pays interest semi-annually. For example, suppose the above bond pays interest semi-annually and the price is 1,197.93. What is the YTM?

FV = 1,000

PV = 1,197.93

n = 20

Pmt = 100

i = ? (4%) ==> note: this is a semi-annual rate; there are two ways to convert it to an annual rate:

1) 4% x 2 = 8% APR (simple interest)

2) (1 + 4%)2 - 1 = 8.16% EAR (compound interest)

Interest Rate Risk

Before discussing interest rate risk, it will be useful to introduce the concept of risk.. Risk, in general, represents the chance that your actual or realized return turns out to be much different than what you expected. (The nominal yield on a Treasury Bill is considered riskless. Why?)

When you buy a bond, the YTM is your expected return if the bond is held to maturity. If interest rates change, your actual return will be different than the YTM. The same is true even if the bond is not held to maturity. There are two sources or kinds of interest rate risk: one is principal risk, the other is reinvestment risk.

Principal risk - the risk that interest rates will rise and decrease the value of your bond

Reinvestment risk - the risk that interest rates will drop so that you must reinvest interim cash flows at a lower rate than the YTM (ytm assumes reinvestment of interest at YTM)


Summary Comments about Interest Rate Risk

1. Everything else equal, bonds with longer maturities are more sensitive to changes interest rates. T7.9 , T7.10

2. Everything else equal, bonds with lower coupons are more sensitive to changes in interest rates. (T7.10)

3. Notice that principal risk and reinvestment risk work in opposite directions.

4. It may be possible that the two completely offset each other. (immunization)

5. The 'measure' of this sensitivity is called duration.

6. Zero coupon bonds can be useful for eliminating interest rate risk.

Other Characteristics of Debt

Debt is not an ownership interest in the firm and creditors usually do not have voting power. Interest on bonds is deductible for tax purposes. (Dividends to shareholders are not.) The written agreement between the the corporation (borrower) and its creditors is called an indenture. The indenture contains basic terms of the bond (coupon, principal amount, repayment times, etc.), a description of any property used as collateral, any call provisions and protective covenants. Call provisions give the issuer the right to repurchase part or all of the issue prior to maturity. Protective covenants are legal restrictions on corporate behavior that either specify things the corporation must do (positive covenants) or things the corporation may not do (negative covenants).

Another risk associated with bonds is default risk. Default risk is the risk that borrowers fail to make all the promised payments. Technical default can occur if the issuer violates any of the debt covenants (contractual agreements) of the bond. Rating agencies (S&P, Moody's) rate the default risk of bonds. (see T7.13) The highest rated bonds are called investment grade. Bonds rated below investment grade are called junk bonds.

The biggest issuer of bonds is the U.S. government. State and local governments also issue bonds. These bonds are municipal bonds. The interest on municipal bonds is exempt from federal taxes. Investors will compare after tax yields of taxable bonds with yields on municipal bonds.

Inflation and Interest Rates


In General: R = r + ¼ + Rp

Where:

R = nominal rate of interest

r = Real Rate Of Interest (S & D Capital)

¼ = Expected Inflation Rate (to Protect Real)

Rp = Risk Premium (Reward For Bearing Risk)


Nominal Rate Of Return: This is the rate you already know how to calculate. It is the percentage change in dollars.

1 + R = FV/PV

FV = PV * (1+R)


Real Rate Of Return: This is the percentage change in goods.

Real Terms - Ie, In Terms Of Goods

1 + r = =

1 + r =

Inflation =

1 + Inflation =

(1 + r) * (1 + ¼) = (1 + R) ==> R = r + ¼ + R¼

 

We drop the last term: ------> R = r + ¼ ( Fisher equation)

Suppose Nominal Did Not Include ¼:

Ex 1: R = 3%; R=3% Pt+1 = $1.06 Pt = $1.00

Start W/ $1.00; Can consume now or save. If save, will have $1.00 X 1.03 = $1.03 in 1 year. What Is actual real rate of return?

1 + r = =

===> R = - 3%

Ex. 2 (Cash)

What Is The Real Rate Of Return On Cash?

R = 0 ===> R = -¼

Determination Of Real Rate Of Interest (See Irving Fisher, The Theory of Interest)

• Time Preference For Consumption

• Investment Opportunities

• Supply And Demand For Capital

Risk Premium. The risk premium may consist of the following sources of risk:

• default risk

• liquidity risk

• interest rate risk (maturity risk)


Term Structure of Interest Rates

The term structure of interest rates is the relation between YTM and time to maturity for a set of zero coupon bonds. The yield curve is a graph of the of the term structure. (There is a technical difference.)

We are interested in why the yield curve, or term structure, has a particular shape. In other words, why is the yield curve either upward or downward sloping? As stated previously, interest rates consist of real rates, expected inflation and a risk premium. We will consider US government bonds, which we assume to be free of default-risk. In this case the risk premium is an interest rate risk premium, reflecting that the longer the maturity the greater is the interest rate risk. (This is called the maturity risk premium in some books.) Expected inflation results in nominal rates containing an inflation premium. The inflation premium is intended to protect lenders' purchasing power. Real rates, which are discussed above, do not move much through time. Thus, changes in interest rates are primarily a result of changes in expected inflation. The inflation premium may rise or fall depending on expected future inflation. If inflation were expected to remain constant, then longer-term rates might still be higher because of the interest rate risk premium.

Summarizing some of the previous discussion, interest rates on bonds consist of the following 'pieces':

• Real rate

• Inflation risk premium

• Interest rate risk premium (maturity premium)

• Default risk premium

• Liquidity risk premium



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