Wash. Rev. Code § 32.32.205
If the deposit balance in any savings account of an eligible account holder or supplemental eligible account holder at the close of business on any annual closing date subsequent to the respective record dates is less than the lesser of (1) the deposit balance in the savings account at the close of business on any other annual closing date subsequent to the eligibility record date or (2) the amount of qualifying deposit as of the eligibility record date or the supplemental eligibility record date, the subaccount balance for the savings account shall be adjusted by reducing the subaccount balance in an amount proportionate to the reduction in the deposit balance. In the event of such a downward adjustment, the subaccount balance shall not be subsequently increased, notwithstanding any increase in the deposit balance of the related savings account. If any such savings account is closed, the related subaccount balance shall be reduced to zero.
RCW 32.32.205