Create a macro function to estimate the Macaulay duration.

  

calculate Macaulay duration is by using the following formula: D 1 + r + [Nx (c r)]) cx [(1+r)N 1] + r) 1+" _1 }-(-/-) 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.