A. The department shall perform and issue the results of sales-ratio studies using sales or appraisal data according to statistical principles that apply to the studies.
B. If the studies disclose discrepancies with county assessors' full cash values, the department may request the assessor or assessors to conduct field appraisals in the county, area, class or classification of discrepancy, using the standard appraisal methods and techniques adopted by the department. Adjustments to property valuations may be based on the results of the assessors' field appraisals.
C. The department shall not issue equalization orders under article 6 of this chapter affecting commercial or industrial property based exclusively on the results of sales-ratio studies.