Measuring Accuracy

Equalization Department - Measuring Accuracy


The Equalization Department reviews assessed values for accuracy every year. The primary measure of accuracy is a median sales ratio. The office analyzes all arms length sales of real property every year and compares the sale price of each property to its assessed value. For example, a property that is assessed at $90,000 and sells for $100,000 has a sales ratio of 90%. This property is assessed at 90% of market value, based upon the indication of one sale. All of these sales ratios are compiled, and a median ratio is calculated. This ratio analysis is performed on a county-wide basis and by individual neighborhood for each property type and will indicate the need to adjust assessed values to a changing market. A single sale of a property does not automatically result in a change to a property assessment, but that one sale might be an indication of more wide-spread changes in the market.

The median level of assessment changes every year depending upon changes in the real estate market and changes in assessments. The median ratio is a primary tool in adjusting assessments to a changing market. Other statistical measures of accuracy and uniformity are performed. These provide information relating to the uniformity of assessed values and also indicate areas in need of review or correction.