Glossary: FI Module 07 — Yield and Spread Measures (Fixed-Rate)

TermDefinition
Effective annual rate (EAR)The annualized rate accounting for compounding:
Annual percentage rate (APR)The stated annual interest rate without compounding adjustment (periodicity × periodic rate)
PeriodicityThe number of compounding periods per year (1 = annual, 2 = semi-annual, 4 = quarterly)
Street conventionYield calculated assuming scheduled coupon dates with no adjustment for weekends or holidays
True yieldYield adjusted for actual payment dates (accounts for weekends/holidays); ≤ street convention
Simple yieldApproximation: (Annual coupon + straight-line amortization of gain/loss) / Price
Government equivalent yieldA corporate bond yield restated on the same day-count basis as government bonds for comparison
G-spreadYield spread over an interpolated government bond yield of the same maturity
I-spreadYield spread over the interpolated swap rate of the same maturity
Z-spread (zero-volatility spread)The constant spread over the spot curve that equates PV of cash flows to the bond’s market price
OAS (option-adjusted spread)Z-spread minus the value of embedded options; represents credit + liquidity spread only
Yield to call (YTC)YTM calculated using the call date and call price instead of maturity and par
Yield to worst (YTW)The lowest of YTM and all possible YTCs; conservative callable bond yield measure
Benchmark rateThe reference yield (government bond or swap rate) used to calculate spreads
Risk premiumThe additional yield above the risk-free rate that compensates for various risks

See also: Yield Measures, Yield Spreads