Understanding Bond Yields
Bond yield is the return an investor realizes on a bond. It's a critical metric for fixed income investors, allowing comparison of bonds with different prices, coupon rates, and maturities. Several types of yields measure different aspects of bond returns.
Bonds are debt instruments where the issuer promises to pay periodic interest (coupon) and return the principal (face value) at maturity. The relationship between bond price and yield is inverse: when prices rise, yields fall, and vice versa.
Types of Bond Yields
Current Yield
Current Yield = Annual Coupon / Current Price x 100
Example: $50 coupon / $950 price = 5.26%
Current yield measures income relative to the current price but ignores capital gains/losses at maturity. It's useful for investors focused on income rather than total return.
Yield to Maturity (YTM)
YTM is the total return anticipated if the bond is held until maturity. It accounts for all coupon payments, the difference between purchase price and face value, and time value of money. YTM is the internal rate of return of a bond.
YTM Assumptions
- Bond is held to maturity
- All coupons are reinvested at the YTM rate
- Issuer makes all payments as scheduled
Yield to Call (YTC)
For callable bonds, YTC calculates return assuming the bond is called at the earliest call date. Investors should compare YTM and YTC to understand potential returns under different scenarios.
Bond Pricing Fundamentals
Premium, Discount, and Par
- Premium Bond: Price > Face Value (YTM < Coupon Rate)
- Discount Bond: Price < Face Value (YTM > Coupon Rate)
- Par Bond: Price = Face Value (YTM = Coupon Rate)
Price-Yield Relationship
Bond prices and yields move inversely. When interest rates rise, existing bonds with lower coupons become less attractive, so their prices fall to increase effective yield. When rates fall, existing higher-coupon bonds become more valuable.
Factors Affecting Bond Yields
Credit Quality
Lower-rated bonds offer higher yields to compensate for default risk. The spread between corporate and Treasury yields reflects perceived credit risk. Investment-grade bonds (BBB/Baa or higher) typically yield less than high-yield (junk) bonds.
Maturity
Longer-maturity bonds generally offer higher yields due to increased interest rate risk and uncertainty. The yield curve plots yields against maturities, typically sloping upward in normal conditions.
Tax Status
Municipal bonds may offer lower nominal yields but higher after-tax yields due to federal and sometimes state tax exemptions. Compare tax-equivalent yields for proper comparison.
Liquidity
Less liquid bonds require higher yields to attract investors. Treasury bonds are highly liquid; corporate bonds and municipal bonds vary in liquidity.
Calculating Bond Price from Yield
Bond Price Formula
Price = Sum of [C / (1 + r)^t] + [F / (1 + r)^n]
Where: C = Coupon payment per period, r = Yield per period, F = Face value, n = Number of periods to maturity
Duration and Yield Sensitivity
Modified Duration
Duration measures bond price sensitivity to yield changes. A duration of 5 means a 1% yield increase causes approximately 5% price decrease. Longer maturity and lower coupons increase duration.
Convexity
Convexity measures how duration changes as yields change. Bonds with higher convexity benefit more from falling rates and suffer less from rising rates.
Bond Yield Strategies
Laddering
Spread investments across different maturities to manage interest rate risk and provide regular reinvestment opportunities. As bonds mature, reinvest at the long end of your ladder.
Barbell Strategy
Concentrate holdings in short-term and long-term bonds, avoiding intermediate maturities. This provides liquidity from short-term holdings and yield from long-term bonds.
Bullet Strategy
Concentrate maturities around a target date. Useful when planning for a specific future expense or liability.
Frequently Asked Questions
Why is YTM different from coupon rate?
YTM reflects total return including capital gains/losses, while coupon rate only shows annual interest as percentage of face value. When bonds trade above or below par, YTM adjusts for the price difference.
Is higher yield always better?
Not necessarily. Higher yields typically indicate higher risk (credit risk, interest rate risk, or liquidity risk). Compare risk-adjusted returns, not just nominal yields.
How do interest rate changes affect bonds?
Rising rates decrease bond prices (and increase yields). The impact is greater for longer-duration bonds. Existing bondholders face capital losses, but new investors get higher yields.
What's the tax-equivalent yield?
For municipal bonds: Tax-Equivalent Yield = Municipal Yield / (1 - Tax Rate). This converts tax-free yield to a comparable taxable yield for proper comparison.