(1) For plan years beginning in 2020, the cost sharing incurred under a health plan for the essential health benefits may not exceed the following amounts:
(a) For self-only coverage:
(i) The amount required under federal law for the calendar year; or
(ii) If there are no cost-sharing requirements under federal law, eight thousand two hundred dollars increased by the premium adjustment percentage for the calendar year.
(b) For coverage other than self-only coverage:
(i) The amount required under federal law for the calendar year; or
(ii) If there are no cost-sharing requirements under federal law, sixteen thousand four hundred dollars increased by the premium adjustment percentage for the calendar year.
(2) Regardless of whether an enrollee is covered by a self-only plan or a plan that is other than self-only, the enrollee's cost sharing for the essential health benefits may not exceed the self-only annual limitation on cost sharing.
(3) For purposes of this section, "the premium adjustment percentage for the calendar year" means the percentage, if any, by which the average per capita premium for health insurance in Washington for the preceding year, as estimated by the commissioner no later than April 1st of such preceding year, exceeds such average per capita premium for 2020 as determined by the commissioner.
(4) Unless preempted by federal law, the commissioner shall adopt any rules necessary to implement this section, consistent with federal rules and guidance in effect on January 1, 2017, implementing the patient protection and affordable care act.