Illinois was one of 14 states where the estimated number of unauthorized immigrants fell between 2009 and 2012, according to a report just out from the Pew Research Center.
http://www.stltoday.com/news/local/govt-and-politics/gateway-to-dc/illinois-one-of-states-where-undocumented-population-fell/article_ec66ec62-baa6-536f-b24d-7bc939de0240.html