EXHIBIT 23 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation by reference of our reports dated April 22, 1999, included in or incorporated by reference in this Form 10-K, into the Company's previously filed Registration Statements on Form S-8 (No. 33-00067, 33-40610, 33-41310, 33-57648, 33-81064, 333-15679, 333-15677, 333-33885 and 333-33897). /s/ ARTHUR ANDERSEN LLP ARTHUR ANDERSEN LLP Chicago, Illinois May 24, 1999