(a) All unallocated liability loss expense payments shall be distributed as follows:
(1) if made in a given calendar year subsequent to the first four years in which an insurer has been issuing liability policies, 35 percent shall be charged to the policies written that year, 40 percent to the policies written in the preceding year, 10 percent to the policies written in the second year preceding, 10 percent to the policies written in the third year preceding and 5 percent to the policies written in the fourth year preceding;
(2) if made in each of the first four calendar years in which an insurer issues liability policies, in the first calendar year 100 percent shall be charged to the policies written in that year; in the second calendar year 50 percent shall be charged to the policies written in that year and 50 percent to the policies written in the preceding year; in the third calendar year 40 percent shall be charged to the policies written in that year, 40 percent to the policies written in the preceding year, and 20 percent to the policies written in the second year preceding; and in the fourth calendar year 35 percent shall be charged to the policies written in that year, 40 percent to the policies written in the preceding year, 15 percent to the policies written in the second year preceding and 10 percent to the policies written in the third year preceding.
(b) A schedule showing such distribution shall be included in the annual statement.