(1) For disability income:

(a) The maximum interest rate for claim reserves is specified in WAC 284-16-520.

(b) Minimum standards with respect to morbidity are those specified in WAC 284-16-500 and 284-16-510; except that, at the option of the insurer, for claims with a duration from date of disablement of less than two years, reserves may 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.

(c) For contracts with an elimination period, the insurer shall measure the duration of disablement as dating from the time that benefits would have begun to accrue had there been no elimination period.

(2) For all other benefits:

(a) The maximum interest rate for claim reserves is specified in WAC 284-16-520.

(b) The insurer shall base the reserve on the insurer's morbidity experience, if such experience is considered credible, or upon other assumptions designed to place a sound value on the liabilities.

(c) General claim reserve methods are as follows:

(i) The insurer may use any generally accepted or reasonable actuarial method or combination of methods to estimate all claim liabilities.

(ii) The methods used for estimating liabilities generally may be aggregate methods, or various reserve items may be separately valued. The insurer may also employ approximations based on groupings and averages. The insurer shall, however, determine adequacy of the claim reserves in the aggregate.