The department may deduct a processing fee for administering direct payments under RCW
41.50.670 according to the dissolution order. The fee may not exceed (1) seventy-five dollars or the actual average administrative costs, whichever is less, for the first disbursement made by the department; and (2) six dollars or the actual average administrative costs, whichever is less for subsequent disbursements. The department shall deduct the fee in equal dollar amounts from the obligee's and obligor's payments. The funds collected pursuant to this section shall be deposited in the department of retirement systems expense account.