The bond market consists of a great number of issuers and types
of securities. To talk about each specific type might fill an
entire textbook; therefore, for the purposes of discussing how
various bond market pricing conventions work, we make the following
major bond classifications:
- U.S. Treasuries: bonds issued by the United
States Department of the Treasury.
- Corporate Bonds: bonds issued by corporations
that carry an investment-grade rating
- Mortgage-Backed Securities (MBS): a bond
collateralized by the cash flows of principal and interest payments
from an underlying pool of single-family residential
mortgages.
- Asset-Backed Securities (ABS): a bond
collateralized by the cash flows of an underlying pool of assets
such as auto loans, credit card receivables, home equity loans,
aircraft leases, etc. The list of assets that have been securitized
into ABSs is almost endless.
- Agency Bonds: debt issued by the
government-sponsored enterprises (GSEs), including Fannie Mae,
Freddie Mac, and the Federal Home Loan Banks.
- Municipal Bonds: a bond issued by a state,
city or local government or its agencies.
A Bond's
Expected Return:
- Yield is the measure used most frequently to estimate or
determine a bond's expected return. Yield is also used as a
relative value measure between bonds. There are two primary yield
measures that must be understood to understand how different bond
market pricing conventions work:
1. yield to maturity and
2. spot rates.
- A yield-to-maturity calculation is made by determining the
interest rate (discount rate) that will make the sum of a bond's
cash flows, plus accrued interest, equal to the current price of
the bond. This calculation has two important assumptions: first,
that the bond will be held until maturity, and second, that the
bond's cash flows can be reinvested at the yield to maturity.
- As we discuss below, spot rates are most often used as a
building block in relative value comparisons for certain types of
bonds.
Benchmarks for
Bonds:
- Most bonds are priced relative to a benchmark. This is where
bond market pricing gets a little tricky. Different bond
classifications, as we have defined them above, use different
pricing benchmarks.
- When the maturity of a bond cannot be known with exactness
because of call or put features, the bond is frequently priced to a
benchmark curve. This is because the estimated maturity of the
callable or put-able bond most likely does not coincide exactly
with the maturity of a specific Treasury.
Yield Spreads
for Bonds:
- A bond's yield relative to the yield of its benchmark is called
a spread. The spread is used both as a pricing mechanism and as a
relative value comparison between bonds.
Types of Bonds
and Their Benchmark Spread Calculation:
- High-Yield Bonds
- High-yield bonds are usually priced at a nominal
yield spread to a specific on-the-run U.S. Treasury bond. However,
sometimes when the credit rating and outlook of a high-yield bond
deteriorates, the bond will start to trade at an actual dollar
price.
- Corporate Bonds
- A corporate bond is usually priced at a nominal yield
spread to a specific on-the-run U.S. Treasury bond that matches its
maturity.
- Asset-Backed Securities
(ABS) - ABS frequently trade at a nominal yield
spread at their weighted average life to the swap curve.
- Agencies -
Agencies frequently trade at a nominal yield spread to a specific
Treasury, such as the on-the-run 10-year Treasury. Callable
agencies are sometimes evaluated based on an OAS where the spot
rate curve(s) are derived from the yields on non-callable
agencies.
Summary:
- Bond market pricing conventions are a little bit tricky, but
understanding the basics removes some of the ambiguity and may even
make it enjoyable. Bond pricing is really just a matter of
identifying a pricing benchmark, determining a spread and
understanding the difference between two basic yield calculations:
yield to maturity and spot rates. With that knowledge,
understanding how various types of bonds are priced shouldn't be
intimidating.
- Bond prices are intrinsically linked to the interest rate
environment in which they trade - with prices falling as interest
rates rise
- Bond prices are also greatly influenced by the creditworthiness
of the issuer, from the federal government down to a junk bond
issuer on the verge of default.
- Bond prices and yields can be calculated in several different
ways, depending on the type of bond and the definition of yield
you're using.
- Benchmarks exist to track bond yields and serve as a relative
measure of price performance.