(35 ILCS 200/16-90)
    Sec. 16-90. Delivery of assessment books. In counties with less than 3,000,000 inhabitants, when the books are completed, the board of review shall deliver one set of the books to the county clerk, who shall file it in his or her office; and one set to the chief county assessment officer. All of the books shall be public records. All assessors' books shall be retained for a period of 5 years, after which the County Board may order the officer having custody of the books to dispose of them and to certify that fact, when completed, to the county board. The assessment completed by the board of review and certified to the county clerk, as equalized, shall be the assessment upon which the taxes of that year shall be extended by the county clerk.
(Source: P.A. 83-1362; 88-455.)