Interest Rates and Bond Valuation
Chapter 6 Interest Rates and Bond Valuation
Key Concepts and Skills
After studying this chapter, you should be able to:
Identify important bond features and types of bonds.
Describe bond values and why they fluctuate.
Discuss bond ratings and what they mean.
Evaluate the impact of inflation on interest rates.
Explain the term structure of interest rates and the determinants of bond yields.
Chapter Outline
6.1: Bonds and Bond Valuation.
6.2: More on Bond Features.
6.3: Bond Ratings.
6.4: Some Different Types of Bonds.
6.5: Bond Markets.
6.6: Inflation and Interest Rates.
6.7: Determinants of Bond Yields.
Bond Definitions
Bond:
A debt contract.
Interest-only loan.
Par value (face value) approximately $1,000.
Coupon rate: The rate of interest the bond pays.
Coupon payment: The actual amount paid to bondholders typically on an annual or semi-annual basis.
Maturity date: The date on which the bond's principal is repaid.
Yield to maturity (YTM): The total return anticipated on a bond if it is held until it matures.
Key Features of a Bond
Par value:
Also known as the face amount.
This amount is repaid at maturity, usually assumed to be $1,000 for corporate bonds.
Coupon interest rate:
The stated interest rate of the bond.
Usually equals the yield to maturity (YTM) at the time of issuance.
To find the coupon payment, multiply the coupon rate by the par value.
Maturity:
Refers to the number of years until the bond must be repaid.
Yield to maturity (YTM):
Represented as “r”.
The market required rate of return for bonds of similar risk and maturity.
It is the discount rate used to value a bond and represents the return if the bond is held to maturity.
Typically equals the coupon rate at the time of issuance.
Quoted as an Annual Percentage Rate (APR).
Current Yield:
Defined as the annual coupon divided by the current price of the bond.
Bond Value
The formula for bond value is:
This expands to:
Important relationships:
As interest rates increase, present values decrease.
As interest rates increase, bond prices decrease, and vice versa.
The Bond-Pricing Equation
The bond-pricing equation for cash flows is formulated as follows:
$C$ = Coupon payment
$F$ = Face value
Practicing Bond Valuation with Texas Instruments BA II Plus
Utilize the following keys:
N = Number of periods to maturity.
I/Y = Period interest rate (YTM).
PV = Present value (The bond value).
PMT = Coupon payment.
FV = Future value (Face value or Par value).
Valuing a Discount Bond with Annual Coupons
Example:
Coupon rate = 10%
Par value = $1,000
Maturity = 5 years
YTM = 11%
Using a calculator:
Input:
5 (N)
11 (I/Y)
100 (PMT)
1000 (FV)
Calculate PV = −963.04
Using formula:
Excel formula: = PV (0.11, 5, 100, 1000, 0).
Note: When YTM > Coupon rate → Price < Par = "Discount Bond".
Valuing a Premium Bond with Annual Coupons
Example:
Coupon rate = 10%
Par value = $1,000
Maturity = 20 years
YTM = 8%
Using a calculator:
Input:
20 (N)
8 (I/Y)
100 (PMT)
1000 (FV)
Calculate PV = −1196.36
Using formula:
Excel formula: = PV (0.08, 20, 100, 1000, 0).
Note: When YTM < Coupon rate → Price > Par = "Premium Bond".
Bond Prices: Relationship Between Coupon and Yield
Understanding the relationships:
When Coupon rate = YTM, Price = Par.
When Coupon rate < YTM, Price < Par; known as a "Discount bond".
When Coupon rate > YTM, Price > Par; known as a "Premium bond".
The Bond-Pricing Equation Adjusted for Semiannual Coupons
Adjustments include:
C = Annual coupon payment → for semiannual
YTM = Annual yield → for semiannual
t = Years to maturity → = Number of six-month periods to maturity.
Semiannual Bonds Example
Example 6.1:
Coupon rate = 14% semiannually.
r = 16%
Maturity = 7 years
Number of coupon payments = 14 (2 x 7 years).
Semiannual coupon payment:
Calculating semiannual yield results in:
Bond value = Using the calculator:
Input:
14 (N)
8 (I/Y)
70 (PMT)
1000 (FV)
Calculate PV = −917.56
Computing Yield-to-Maturity (YTM)
Yield-to-maturity (YTM) is defined as follows:
The market required rate of return implied by the current bond price.
Calculator steps:
Enter N, PV, PMT, and FV.
Remember the sign convention:
PMT and FV must share the same sign.
PV is the opposite sign (negative).
Calculate using CPT I/Y for the yield.
YTM with Annual Coupons
Example:
Consider a bond with:
Coupon rate = 10%
15 years to maturity
Par value = $1,000
Current price = $928.09
Market yield deduction:
Using calculator inputs for YTM computation:
15 (N)
−928.09 (PV)
1000 (FV)
100 (PMT)
YTM = 11%
YTM with Semiannual Coupons
Suppose a bond has:
Coupon rate = 10% (semiannual)
Face value = $1,000
Maturity = 20 years
Current price = $1,197.93
Calculate YTM using:
Inputs:
40 (N = 20 years x 2)
−1197.93 (PV)
1000 (FV)
50 (semiannual PMT = $100 \div 2)
Result: Semiannual yield = 4%, hence YTM = 8%.
Summary of Bond Valuation (Table 6.1)
The valuation of a bond is summarized:
Where:
C = Coupon paid each period.
r = Rate per period.
t = Number of periods.
F = Bond’s face value.
Is It Debt or Equity?
Debt:
Not an ownership interest.
No voting rights.
Interest is tax-deductible.
Creditors have legal recourse if interest or principal payments are missed.
Excess debt may lead to financial distress and bankruptcy.
Equity:
Ownership interest in the firm.
Common stockholders vote for board members.
Dividends paid are not tax-deductible.
Dividends are not liabilities until declared.
Stockholders do not have recourse if dividends are not declared.
An all-equity firm cannot go bankrupt.
The Bond Indenture
The bond indenture, or "Deed of Trust," is a contract containing:
Basic terms of the bonds.
Total amount of bonds issued.
Whether the bonds are secured or unsecured.
Sinking fund provisions.
Call provisions, including deferred call and call premium.
Protective covenants.
Bond Ratings – Investment Quality
High Grade:
Moody’s Aaa and S&P AAA – extremely strong capacity to pay.
Moody’s Aa and S&P AA – very strong capacity to pay.
Medium Grade:
Moody’s A and S&P A – strong capacity to pay, but more susceptible to changes.
Moody’s Baa and S&P BBB – adequate capacity to pay, with adverse conditions impacting ability to pay.
Bond Ratings – Speculative
Low Grade:
Moody’s Ba, B, Caa and Ca.
S&P BB, B, CCC, CC.
Considered speculative regarding capacity to pay; "B" ratings are the lowest degree of speculation.
Very Low Grade:
Moody’s C and S&P C – income bonds with no interest paid.
Moody’s D and S&P D – in default with principal and interest in arrears.
Government Bonds
Treasury Securities = Federal government debt:
Treasury Bills (T-bills): Pure discount bonds with a maturity of one year or less.
Treasury notes: Coupon debt with maturity between one and ten years.
Treasury bonds: Coupon debt with maturity greater than ten years.
Government Bonds - Municipal Securities
Municipal Securities are:
Debt of state and local governments.
Varying degrees of default risk and rated similarly to corporate debt.
Interest received is tax-exempt at the federal level and usually exempt from state tax in the issuing state.
Example 6.4: Tax Consideration
A taxable bond yields 8% and a municipal bond yields 6%.
In a 40% tax bracket:
After-tax return on corporate bond: 8%(1 − 0.4) = 4.8%.
Municipal bond return: 6%.
At what tax rate would be indifferent? Setting:
8%(1 - t) = 6% → t = 25%.
Zero Coupon Bonds
Characteristics:
Make no periodic interest payments (coupon rate = 0%).
Yield to maturity comes from the difference between purchase price and par value (capital gains).
Cannot be sold for more than par value.
Also referred to as zeroes or deep discount bonds.
Examples include Treasury Bills and US Savings bonds.
Floating Rate Bonds
Definition:
Coupon rate floats based on an index value.
Examples: Adjustable rate mortgages and inflation-linked Treasuries.
Advantages:
Less price risk as coupon adjusts, maintaining closeness to yield to maturity.
Coupons may have a "collar" limiting the maximum and minimum rates.
Bond Markets
Market characteristics:
Primarily consist of over-the-counter (OTC) transactions with electronically connected dealers.
Although a large number of bond issues exist, daily volume for individual issues is often low.
Obtaining current prices can be challenging, especially for small company or municipal bonds.
Treasury securities are an exception with more consistent pricing.
Inflation and Interest Rates
Key definitions:
Real rate of interest: Represents a change in purchasing power.
Nominal rate of interest: Quoted rate of interest, reflecting changes in purchasing power and inflation.
The ex ante nominal rate includes desired real return plus an adjustment for expected inflation.
The Fisher Effect
Definition:
The Fisher effect illustrates the relationship among real rates, nominal rates, and inflation defined mathematically as:
$R$ = Nominal rate (Quoted rate).
$r$ = Real rate.
$h$ = Expected inflation rate.
Approximates as:
Example 6.6: Calculation of Nominal Rate
If a real return of 10% is required and expected inflation is 8%, calculate the nominal rate:
Actual Calculation:
R = (1.10)(1.08) - 1 = 0.1880, ext{ or } 18.80 ext{%}.
Using approximation:
R = 10 ext{%} + 8 ext{%} = 18 ext{%}.
Note: The difference between actual Fisher effect and approximation is significant when real return and inflation are relatively high.