The corporation shall maintain at all times reserves adequate to provide the hospital, medical-surgical and other health services made available to its members and beneficiaries and to meet all its costs and expenses. The reserves shall not be less than an amount equal to two months of benefit payments and administrative expenses, based on an average of the preceding twelve months, or if the reserves are not equal to such average, they must have been increased during the preceding twelve months by an amount equal to one percent of the gross dues income during such period. The determination of minimum reserves hereunder shall be subject, as to amounts payable to participating providers of the health services, to any right of the corporation to prorate the amounts under the terms of its health service contracts with providers. The director may decrease or suspend the requirements of this section if he finds that such action would be in the best interest of the members of the corporation.