If we assume that, we cannot solve the problem, because we don’t have yields for 9 months, 15 months, and 21 months.
If they haven’t specified the frequency of coupon payments, I suspect that they want us to use semiannual payments. I was simply hoping that they’d made that explicit.
One approach as follows provides zeros of 2.1508% (for year 1), 2.2529% (year 1.5), and 2.4031% (year 2)
Step one. Determined coupon payment frequency for bonds 3 through 5 is semi annual by checking consistency between bond price and quoted yield.
Step two. Solve for 1 Year Zero. First two bonds provide zero for 0.25, 0.5 years respectively. We will use the rate for 0.5 years to discount the first coupon and then solve for 1.0 year discount rate (which is the one year zero);
PV of One Year Bond = PMT1/(1+zero_half_year)0.5 + PMT2/(1+zero_year1)1
100.3557 = 1.25/(1.020202)0.5 +101.25/(1+r) Solving for r = 2.1508% is the year 1 zero
Step three. With the 0.5 year and one year zeros we can go ahead and solve for the 1.5 year zero;
102.5857=2/(1.020202)0.5 + 2/(1.021508) +102/(1+r(1.5years))1.5 Solving for r(1.5years) is 2.2529%
Freaky guy: The first two bonds (0.25, 0.5 years) have no coupon. Therefore I took their quoted yields as the zero rates for 0.25 and 0.5 years respectively.
I have not gotten around to solving the forward rate part of the question. However, one can solve it using the forward rate model equation.
In general, if you have the m-period spot rate, sm, and the (m+1)-period spot rate, sm+1, then the 1-period forward rate starting m periods from today. 1fm is calculated by:
1 + 1fm = (1 + sm+1)m+1 / (1 + sm)m
However, there’s still the problem of how these rates are quoted, which is inconsistent. You need effective rates to use in the formula I wrote, but the rates you’re given aren’t (necessarily) effective rates.
Two comments: I agree with S2000 this question is incomplete - we need to know the compounding periods as the numbers are inconsistent.
That said, if the bonds are semi-annual then I think a correction to my earlier post is warranted. If bonds 3 to 5 are semi-annual, there are two periods per year. Two years = 4 periods. Therefore the spot for each period is found sequentially by equating the bond PV to the PMTs discounted by the spot rates. It is then annualized.
For instance, the spot for year one is found with:
100.3557 = 1.25/(1.010101)1 +101.25/(1+r(2))2
r(2) is the discount rate for the second period which is the second half year. Multiply by 2 to obtain the annualized value for the spot rate for year one.