(1) When a title insurer files rates with the commissioner, the title insurer must demonstrate that the proposed rates comply with RCW 48.29.143. To the extent possible:

(a) Each title insurer must provide credible data to support the proposed rates. If credible data are not available, the title insurer must provide supporting documentation that describes its process for developing the proposed rates and demonstrates that they meet the requirements of RCW 48.29.143.

(b) Data used to support the proposed rates should be from the state of Washington. If data from other states are used, the title insurer must explain why those data are similar to what would be expected in Washington.

(2) If a title insurer proposes to use rates that are identical to the rates of another title insurer, the rate filing must include supporting information that demonstrates that the title insurer's proposed rates meet the requirements of RCW 48.29.143. It is not sufficient simply to state that the proposed rates are identical to those of another title insurer or that the rates are being filed for competitive purposes.

(3) Under RCW 48.29.143(2), a title insurer's provision for underwriting profit must be consistent with its cost of capital. The rate filing must demonstrate that expected underwriting profit, plus expected investment income on reserves and surplus, minus expected federal income taxes corresponds to an appropriate target after-tax rate of return on the title insurer's equity or net worth.

(4) The rate filing must provide sufficient information so that the commissioner may determine whether the proposed rates comply with RCW 48.29.147(3).