Oregon Revised Statutes Insurance § 733.060

(1) Every insurer shall maintain an unearned premium reserve on all policies in force.

(2) The Director of the Department of Consumer and Business Services may require that such reserves shall be equal to the unearned portions of the gross premiums in force as calculated pro rata on each respective risk from the policy's date of issue. In the absence of such requirement, the unearned premium reserve shall be equal to the pro rata unearned portions of the gross premiums in force as calculated by an approximation method approved by the director. After adopting a method of computing such reserves, an insurer shall not change methods without approval of the insurance supervisory official of the insurer's domicile.

(3) This section does not apply to: