(1) Disability income benefits due to accident or sickness.

(a) Contract reserves for:

(i) Contracts issued prior to January 1, 1993: The same basis, if any, as that employed by the insurer as of December 31, 1992;

(ii) Contracts issued on or after January 1, 1993: The 1987 Commissioners Group Disability Income Table (87CGDT).

(b) Claim reserves for:

(i) Claims incurred on or after January 1, 1993: The 1987 Commissioners Group Disability Income Table (87CGDT);

(ii) Claims incurred prior to January 1, 1993: Optional use of either the 1964 Table or the 1987 Table.

(2) Other group contract benefits.

(a) Contract reserves: For all other group contract benefits, morbidity assumptions are to be determined using tables established for reserve purposes by a qualified actuary and acceptable to the commissioner.

(b) Claim reserves: For all benefits other than disability, claim reserves are to be based on the insurer's experience, if such experience is considered credible, or upon other assumptions designed to place a sound value on the liabilities.