25 ILCS 82/20
The note shall be factual in nature, as brief and concise as may be, and shall provide a reliable estimate in dollars, and, in addition, it shall include both the immediate effect and, if determinable or reasonably foreseeable, the long range effect of the measure. A housing affordability impact note shall be prepared on the basis of a single family residence and may include an estimate for a larger development as an analysis of the long range effect of a measure. If, after careful investigation, it is determined that no dollar estimate is possible, the note shall contain a statement to that effect, setting forth the reasons why no dollar estimate can be given. A brief summary or work sheet of computations used in arriving at housing affordability impact note figures shall be included.
25 ILCS 82/20