Kevin Crotty
BUSI 448: Investments
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Today:
Two methods to get them:
If \(z_1\), \(z_2\), …, \(z_T\) are maturity-specific riskless spot rates, then the bond price is:
\[ P(\mathbf{z}) = \frac{C/m}{(1+z_1)} + \frac{C/m}{(1+z_2)^2} + ... + \frac{C+FACE}{(1+z_T)^T} \]
\[ P(\mathbf{z}) = \sum_{t=1}^T\frac{C/m}{(1+z_t)^t} + \frac{FACE}{(1+z_T)^T} \]
where
Bootstrapping: method of extracting spot rates from coupon bond prices.
Iterative procedure: 1st solve for \(z_1\), then \(z_2\) using \(z_1\)…
To get spot rate \(z_t\), we must know \(z_1\),\(z_2\), …, \(z_{t-1}\): \[z_t = \left(\frac{CF_t}{PV(CF_t)}\right)^{1/t}-1\]
\(PV(CF_t) = P_t - \sum_{i=1}^{t-1} \frac{CF_i}{(1+z_i)^i}\)
\(P_t\) is the price of the coupon bond maturing at time \(t\).
Bond | Price | Coupon Rate | Maturity | Face Value |
A | 97.5 | 0% | 0.5 | 100 |
B | 95 | 0% | 1.0 | 100 |
C | 955 | 2.5% | 1.5 | 1,000 |
D | 1,000 | 5.75% | 2 | 1,000 |
Assume semiannual coupon payments and no credit risk.
BUSI 448