A self-insurer may designate itself to be the principal reporting entity and report closed claim data on behalf of itself and any excess insurer. If the self-insurer designates itself to be the principal reporting entity, the self-insurer must:

(1) Notify the commissioner in writing of this arrangement;

(2) Report closed claim data required under chapter 48.140 RCW and this chapter on behalf of itself and the excess insuring entity; and

(3) Accept responsibility for compliance with RCW 48.140.020(2).