Wisconsin Statutes Statistics (Ch. 69) § 69.63. Department of revenue, duties

It shall be the duty of the department of revenue to collect from time to time statistics of recorded sales of real estate in each county and of the assessed valuation of the lands included in such sales. In collecting such statistics, sales appearing to be made for a nominal consideration or as to which the true consideration is not stated and cannot be readily ascertained, and those in which the description of lands does not substantially correspond or cannot be identified with descriptions upon the assessment roll, shall be omitted; and the department may also exclude from such statistics any other sales where for any reason the data appear to be unreliable or not serviceable.