55 ILCS 5/6-2007
Anticipatory obligations issued against taxes levied for any purpose shall not be in excess of 85% of such taxes extended or to be extended, computed upon the then last equalized valuation determined by the Department of Revenue of the State of Illinois.
In any county in which there shall have been created a working cash fund pursuant to the provisions of Division 6-27, notes shall at no time be issued in anticipation of the collection of taxes levied for general corporate purposes for any year, under the provisions of this Division, for such an amount that the aggregate of (a) the amount of such notes, and the interest to accrue thereon, (b) the aggregate of such notes theretofore issued in anticipation of the collection of such taxes for such year, and the interest accrued and to accrue thereon, (c) the aggregate amount of warrants theretofore drawn in anticipation of the collection of such taxes for such year, and the interest accrued and to accrue thereon, under the provisions of "An Act of the Constitution of the State of Illinois to provide for the manner of issuing warrants upon the treasurer of the State or of any county, township, city, village or other municipal corporation and jurors' certificates," approved June 27, 1913, as amended, and (d) the aggregate amount of money theretofore transferred from the working cash fund of such county to the general corporate fund thereof, shall exceed ninety (90) per centum of the actual or estimated amount of such taxes extended or to be extended by the county clerk upon the books of the collector or collectors of State and county taxes within such county.
55 ILCS 5/6-2007