1. (1) A multivariate statistical analysis must evaluate the rating factors listed below (if applicable to the rating plan, and to the extent that data are credible):

   1. (a) For homeowners, dwelling property, earthquake, and personal inland marine insurance:

      1. (i) Insurance score;
      2. (ii) Territory and/or geographic area;
      3. (iii) Protection class;
      4. (iv) Amount of insurance;
      5. (v) Surcharges or discounts based on loss history;
      6. (vi) Number of family units; and
      7. (vii) Policy form relativity.

   2. (b) For private passenger automobile, personal liability and theft, and mechanical breakdown insurance:

      1. (i) Insurance score;
      2. (ii) Driver class;
      3. (iii) Multicar discount;
      4. (iv) Territory and/or geographic area;
      5. (v) Vehicle use;
      6. (vi) Rating factors related to driving record; and
      7. (vii) Surcharges or discounts based on loss history.

2. (2) An insurer must provide a general description of the model used to perform the multivariate analysis, including the:

   1. (a) Formulas the model uses;
   2. (b) Rating factors that are included in the modeling process; and
   3. (c) Output from the model, such as indicated rates or rating factors.
3. (3) An insurer must show how the proposed rates or rating factors are related to the multivariate analysis.

[Statutory Authority: RCW 48.02.060(3). WSR 23-03-018 (Matter R 2022-08), § 284-24A-050, filed 1/6/23, effective 2/6/23. Statutory Authority: RCW 48.02.060, 48.18.480, 48.19.020, 48.19.035, 48.19.080. WSR 22-04-090 (Matter R 2021-07), § 284-24A-050, filed 2/1/22, effective 3/4/22. Statutory Authority: RCW 48.02.060, 48.18.545, 48.19.035, and 48.30.010. WSR 05-02-026 (Matter No. R 2004-01), § 284-24A-050, filed 12/29/04, effective 7/1/05. Statutory Authority: RCW 48.02.060, 48.18.100, 48.18.120, 48.19.080, 48.19.370, 48.30.010, 49.60.178, 48.18.545(7), 48.19.035(5). WSR 02-19-013 (Matter No. R 2001-11), § 284-24A-050, filed 9/6/02, effective 10/7/02.]