The Board of Trustees shall credit to the expense fund of each State system its pro rata share of: the amount attributable to the administrative and operational expenses of the Board of Trustees and the State Retirement Agency as certified by the Board of Trustees under § 21–125 of this title; the amounts authorized by the Board of Trustees under this section for investment management services, including personnel and operational expenses of the Investment Division; and the amount authorized by the Board of Trustees to implement a closing agreement with the Internal Revenue Service regarding former members of the Employees’ Retirement System or the Teachers’ Retirement System who elected to become members of or participate in those State systems under former Article 73B, §§ 2–206 and 3–206 of the Code. The Board of Trustees shall pay from the expense fund of each State system its pro rata share of: the administrative and operational expenses of the Board of Trustees and the State Retirement Agency, in accordance with the annual State budget; the amounts as authorized by the Board of Trustees necessary for investment management services, including personnel and operational expenses of the Investment Division; and the amounts as authorized by the Board of Trustees necessary to implement a closing agreement with the Internal Revenue Service regarding former members of the Employees’ Retirement System or the Teachers’ Retirement System who elected to become members of or participate in those State systems under former Article 73B, §§ 2–206 and 3–206 of the Code. The amounts for the personnel and operational expenses of the Investment Division shall be paid out of the accumulation fund of each State system on a pro rata basis. Each year the Board of Trustees shall estimate the amount, not exceeding 0.22% of active member payroll, retiree benefits, and former member compensation, necessary for the administrative and operational expenses of the Board of Trustees and the State Retirement Agency. Each quarter of the fiscal year the Board of Trustees shall estimate one–fourth of an amount, not exceeding 0.5% of the market value as of the last day of the preceding quarter of invested assets that are externally managed exclusive of assets invested in real estate or alternative investments, necessary to procure and retain investment management services other than external real estate or alternative investment management services. The Board of Trustees is not limited in the amount of investment manager fees that the Board of Trustees may pay as necessary for external real estate or alternative investment management services. The amounts estimated under subsection (c) of this section shall be paid into the expense funds of the several systems during the ensuing year on a pro rata basis according to the total membership of each system. The amounts estimated under subsection (d) of this section shall be paid into the expense funds of the several systems during the ensuing year on a pro rata basis according to the total assets held by each system. The Board of Trustees may combine the expense funds of the several systems for budgetary and administrative efficiency. On or before December 31 of each year, the Board of Trustees shall report to the General Assembly the actual amount spent for investment management services during the preceding fiscal year. The report required under subparagraph (i) of this paragraph shall include the amount of carried interest on any assets of the system. On or before December 31 each year, the Board of Trustees shall report to the General Assembly the actual amount spent for Investment Division operations during the preceding fiscal year.