Every health maintenance organization shall, when determining liabilities, include an amount estimated in the aggregate to provide (1) for any unearned premium, (2) for the payment of all claims for health care expenditures which have been incurred, whether reported or unreported, which are unpaid, and for which such organization is or may be liable, and (3) for the expense of adjustment or settlement of such claims. Such liabilities shall be computed in accordance with rules and regulations adopted and promulgated by the director upon reasonable consideration of the ascertained experience and character of the health maintenance organization.