NEW YORK (Standard&Poor's) April 19, 2013--Standard&Poor's Ratings Services today affirmed its 'A+/A-1' rating on Illinois Development Finance Authority's (the issuer's) adjustable demand revenue bonds series 1999 (for the Chicago Horticultural Society project) due Jan. 1, 2029. The affirmation follows our review of documents related to the expected replacement of the letter of credit (LOC) currently provided by JPMorgan Chase Bank N.A. ('A+/A-1') with a new LOC from The Northern Trust Co. ('AA-/A-1+'). The long- and short-term components of our current rating reflect our long- and short-term issuer credit ratings on JPMorgan Chase Bank N.A. On the LOC replacement date, which is currently scheduled for June 6, 2013, the long- and short-term components of our rating will