If, by reason of a reduction in benefits under title XVIII of the Social Security Act, the level of health benefits under the Combined Fund would be reduced, the trustees of the Combined Fund shall increase the per beneficiary premium for the plan year in which the reduction occurs and each subsequent plan year by the amount necessary to maintain the level of health benefits which would have been provided without such reduction.
For planyears ending on or before September 30, 2006, the unassigned beneficiaries premium for any assigned operator shall be equal to the applicable percentage of the product of the per beneficiary premium for the plan year multiplied by the number of eligible beneficiaries who are not assigned under section 9706 to any person for such plan year.
For planyears beginning on or after October 1, 2006, subject to subparagraph (B), there shall be no unassigned beneficiaries premium, and benefit costs with respect to eligible beneficiaries who are not assigned under section 9706 to any person for any such plan year shall be paid from amounts transferred under section 9705(b).
If, for any planyear beginning on or after October 1, 2006, the amounts transferred under section 9705(b) are less than the amounts required to be transferred to the Combined Fund under subsection (h)(2)(A) or (i) of section 402 of the Surface Mining Control and Reclamation Act of 1977 (30 U.S.C. 1232), then the unassigned beneficiaries premium for any assigned operator shall be equal to the operator’s applicable percentage of the amount required to be so transferred which was not so transferred.
The trustees of the Combined Fund shall establish and maintain 3 separate accounts for each of the premiums described in subsections (b), (c), and (d). Such accounts shall be credited with the premiums received and amounts transferred under section 9705(b) and debited with expenditures allocable to such premiums.
Except as provided in subparagraph (B), if, for any planyear, there is a shortfall or surplus in any premium account, the premium for the following plan year for each assigned operator shall be proportionately reduced or increased, whichever is applicable, by the amount of such shortfall or surplus. Amounts credited to an account from amounts transferred under section 9705(b) shall not be taken into account in determining whether there is a surplus in the account for purposes of this paragraph.
The term “applicable percentage” means, with respect to any assigned operator, the percentage determined by dividing the number of eligible beneficiaries assigned under section 9706 to such operator by the total number of eligible beneficiaries assigned under section 9706 to all such operators (determined on the basis of assignments as of October 1, 1993).
The annual premium under subsection (a) for any planyear shall be payable in 12 equal monthly installments, due on the twenty-fifth day of each calendar month in the plan year. In the case of the plan year beginning February 1, 1993, the annual premium under subsection (a) shall be added to such premium for the plan year beginning October 1, 1993.
The trustees of the Combined Fund shall, not later than 60 days after the enactment date, furnish to the Commissioner of Social Security information as to the benefits and covered beneficiaries under the fund, and such other information as the Secretary  may require to compute any premium under this section.
During the planyear of the Combined Fund beginning February 1, 1993, the 1988 agreement operators shall make contributions to the Combined Fund in amounts necessary to pay benefits and administrative costs of the Combined Fund incurred during such year, reduced by the amount transferred to the Combined Fund under section 9705(a) on February 1, 1993.
During the period beginning February 1, 1993, and ending September 30, 1994, the 1988 agreement operators shall make contributions to the Combined Fund as are necessary to pay off the expenses accrued (and remaining unpaid) by the 1950 UMWA Benefit Plan and the 1974 UMWA Benefit Plan as of February 1, 1993, reduced by the assets of such plans as of such date.
In the case a 1988 agreement operator making contributions under subparagraph (B), the premium of such operator under subsection (a) shall be reduced by the amounts which are paid to the Combined Fund by reason of claims arising in connection with the 1950 UMWA Benefit Plan and the 1974 UMWA Benefit Plan as of February 1, 1993, including claims based on the “evergreen clause” found in the language of the 1950 UMWA Benefit Plan and the 1974 UMWA Benefit Plan, and which are allocated to such operator under subparagraph (E).
Clause (ii) shall not apply to the extent the amounts paid exceed the contributions.
Contributions under subparagraphs (A) and (B), and premium reductions under subparagraph (D)(ii), shall be made ratably on the basis of aggregate contributions made by such operators under the applicable 1988 coal wage agreements as of January 31, 1993.
A person shall not fail to be treated as an assigned operator to which this subsection applies solely because the person ceases to be an assigned operator by reason of section 9706(h)(1) if the person otherwise meets the requirements of this subsection and is liable for the payment of premiums under section 9706(h)(3).
For purposes of this subsection, the term “controlled group of corporations” has the meaning given such term by section 52(a).