(1) Introduction. This rule explains the stratification process for real property. The stratification process is the grouping of real property within each county into homogeneous classifications based upon certain criteria in order to obtain representative samples. Stratification is used in determining the number of appraisals to be included in the ratio study and also for ratio calculation. The county's most current certified assessment rolls are used for stratification. Counties must stratify rolls using a land use code stratification system as prescribed by the department. (See RCW 36.21.100.)

(2) Stratification - Parcel count and total value - Exclusions. The stratification of the real property assessment rolls must include a parcel count and a total value of the taxable real property parcels in each stratum, excluding the following:

(a) Designated forest lands.(See chapter 84.33 RCW);

(b) Timberland classified under chapter 84.34 RCW. (See RCW 84.34.060);

(c) Current use properties in those counties where a separate study is conducted pursuant to WAC 458-53-095(3);

(d) State assessed properties; and

(e) State-owned game lands as defined in RCW 77.12.203(2).

(3) Stratification - By county. For the real property ratio study, the assessment roll must be stratified for individual counties according to land use categories and substratified by value classes as determined by the department. Stratification will be reviewed at least every other year by the department to determine if changes need to be made to improve sampling criteria. After the strata have been determined, the department will notify the counties of the strata limits, and each county must provide the department with the following, taken from the county's assessment rolls:

(a) A representative number of samples, as determined by the department, in each stratum, together with:

(i) The name and address of the taxpayer for each sample;

(ii) The land use code for each sample;

(iii) The previous year's assessed value for each sample;

(iv) The current year's assessed value for each sample; and

(v) The actual number of samples;

(b) The total number of real property parcels in each stratum; and

(c) The total assessed value in each stratum for both the previous year and the current year.

(4) Counties to provide information timely. The stratification information described in subsection (3) of this rule must be provided by the counties to the department in a timely manner to enable the department to certify the preliminary ratios in accordance with WAC 458-53-200(1). Failure to provide the information in a timely manner will result in the department using its best estimate of stratum values to calculate the real property ratio.

(5) Standard two-digit land use code. The following two-digit land use code will be used as the standard to identify the actual use of the land. Counties may elect to use a more detailed land use code system using additional digits, however, no county land use code system may use fewer than the standard two digits.