§ 35.018 AMOUNTS ELIGIBLE FOR EXEMPTION.
   The amount of actual value added which is eligible to be exempt from taxation shall be as follows:
   (A)   For the first year, 75%;
   (B)   For the second year, 60%;
   (C)   For the third year, 45%;
   (D)   For the fourth year, 30%; and
   (E)   For the fifth year, 15%.
(Iowa Code § 427B.3) (1999 Code, § 8.04)