Write a macro function to estimate the Macaulay duration. Use the values given on sheet

$$P$3$a$$ to test your functionAnother way to calculate Macaulay duration is by using the

following formula:

$D=\{\frac{1+r}{r}-\frac{1+r+[N(c-r)]}{c[(1+r{)}^N-1]+r}\}-(\frac{t}{T})$

where $c$ is the coupon rate per period.

The Macaulay duration is usually expressed in annual

terms. To convert it to an annual duration, divide the

Macaulay duration by the number of coupon payment

periods per year.