35 ILCS 200/18-240

(a) The township assessor, the multi-township assessor, the chief county assessment officer, the board of review, and the board of appeals shall cause the assessed value attributable to new property to be entered and certified in the assessment books under rules promulgated by the Department. (b) For the levy year in which this Law first becomes applicable to a county pursuant to Section 18-213, the chief county assessment officer shall certify to the county clerk, after all changes by the board of review or board of appeals, as the case may be, the assessed value of new property by taxing districts for that levy year under rules promulgated by the Department.