A rate is not excessive if the rate is not unreasonably high relative to the following elements, individually or collectively; provision for anticipated benefit costs; provision for administrative expense; provision for cost transfers, if any; provision for a contribution to or from surplus that is consistent with the attainment or maintenance of adequate and unimpaired surplus as provided in section 204a; and provision for adjustments due to prior experience of groups, as defined in the group rating system. A determination as to whether a rate is excessive relative to these elements, individually or collectively, shall be based on the following: reasonable evaluations of recent claim experience; projected trends in claim costs; the allocation of administrative expense budgets; and the present and anticipated unimpaired surplus of the health care corporation.