On or before the third Monday in December, annually, the county collector shall make out and file with the county clerk a detailed list of errors in assessment of property and errors in footing of tax books, giving in each case a description of the property, the valuation and amount of each tax and special assessment, and cause of error. County collectors, in cases of removals and bankruptcies of taxpayers, may give the same cause for the inability to collect as sworn to by the township collectors, stating in their return that such was the statement made by the township collector, and that the tax still remains uncollected.
35 ILCS 200/20-165