On Thursday, the Illinois Department of Revenue released the final 2015 Cook County equalization factor.  The multiplier for 2015 is 2.6685.  The press release from the Department of Revenue is available here. 

As the following chart demonstrates, the final Cook County equalization factors have been on a bit of a rollercoaster ride for the past dozen years, with 2009 being the peak year and factors trending downward since then.

The Property Tax Code requires the Department to issue a multiplier that, when applied to the assessed value of all property in a county (except for specially assessed property such as farmland), will result in the aggregate assessed value of all property in the County being 33.33% of the property’s fair cash value.  This equalization of assessed values is accomplished by comparing recorded sales prices to assessed values for the three prior years, and it is done in an effort to implement property tax limitations and certain state funding programs fairly.