What is Mass Appraisal?

Mass appraisal is the systematic appraisal of groups of properties as of a given date using standardized procedures and statistical testing. This differs from single-property appraisal, commonly referred to as "fee" or "bank" appraisal, which normally deals with only a particular property as of a given date.

Mass appraisal includes the application of single-property appraisals, as well as the development of appraisal formulas and statistical models, that can be applied uniformly to a number of properties at a time.

The Mandan Assessing Department annually selects areas of town or types of properties that are in need of reappraisal. For those, staff appraisers and data collectors inspect each property and perform a new appraisal on each.

The department also performs continual statistical analysis on property sales and current appraisals to determine if assessment values are inline with what properties are selling for. If not, values are trended to the market by several different means.