(1) Following the close of each accounting year, the pool administrator shall determine the total net cost of pool operation which shall include:

(a) Net premium (premiums less administrative expense allowances), the pool expenses of administration, and incurred losses for the year, taking into account investment income and other appropriate gains and losses; and

(b) The amount of pool contributions specified in the state Omnibus Appropriations Act for deposit into the health benefit exchange account under RCW 43.71.060, to assist with the transition of enrollees from the pool into the health benefit exchange created by chapter 43.71 RCW.

(2) Each member's proportion of participation in the pool shall be determined annually, by the board based on annual statements and other reports deemed necessary by the board and filed by carriers with the commissioner, by multiplying the total cost of pool operation by a fraction. The numerator of the fraction equals that member's total number of resident insured persons, including spouse and dependents, covered under all health plans in the state by that member during the preceding calendar year. The denominator of the fraction equals the total number of resident insured persons, including spouses and dependents, covered under all health plans in the state by all pool members during the preceding calendar year.

(a) All carriers that meet the definition of a member, regardless of whether they actually provided applicable health coverage during the accounting year, must file these statements and other reports.

(b) For purposes of calculating the numerator and the denominator under this subsection:

(i) All health plans in the state by the state health care authority include only the uniform medical plan;

(ii) Each ten resident insured persons, including spouse and dependents, under a stop loss plan or the uniform medical plan shall count as one resident insured person; and

(iii) Health plans serving medical care services program clients under RCW 74.09.035 are exempted from the calculation.

(c) Except as provided in RCW 48.41.037, any deficit incurred by the pool, including pool contributions for deposit into the health benefit exchange account, shall be recouped by assessments among members apportioned under this subsection pursuant to the formula set forth by the board among members. The monthly per member assessment may not exceed the 2013 assessment level of $2.57. If the maximum assessment is insufficient to cover a pool deficit, the assessment shall be used first to pay all incurred losses and pool administrative expenses, with the remainder being available for deposit in the health benefit exchange account.

(3)(a) The board may abate or defer, in whole or in part, the assessment of a member if they determine that payment of the assessment would endanger the ability of the member to fulfill its contractual obligations.

(b) If an assessment against a member is abated or deferred, in whole or in part, the amount by which such assessment is abated or deferred may be assessed against the other members in a manner consistent with the basis for assessments set forth in subsection (2) of this section. The member receiving such abatement or deferment shall remain liable to the pool for the deficiency.

(4)(a) Subject to the limitation imposed in subsection (2)(c) of this section, the pool administrator shall transfer the assessments for pool contributions for the operation of the health benefit exchange to the treasurer for deposit into the health benefit exchange account.

(b) If assessments exceed actual losses and administrative expenses of the pool and pool contributions for deposit into the health benefit exchange account, the excess shall be held at interest and used by the board to offset future losses or to reduce pool premiums. As used in this subsection, "future losses" includes reserves for incurred but not reported claims.