In theory CDS spreads should be closely related to bond yield spreads. Define y as the
yield on an n-year par yield bond issued by a reference entity, r as the yield on an n-year
par yield riskless bond, and s as the n-year CDS spread. The cash flows from a portfolio
consisting of the n-year par yield bond issued by the reference entity and the n-year credit
default swap are very close to those from the n-year par yield riskless bond in all states of
the world. The relationship