Chicago Mayor Richard M. Daley proclaimed August 10, 2005 to be "House Unity Day" in Chicago, in celebration of the "21st anniversary of house music" (actually the 21st anniversary of the founding of Trax Records, an independent Chicago-based house label). The proclamation recognized Chicago as the original home of house music and that the music's original creators "were inspired by the love of their city, with the dream that someday their music would spread a message of peace and unity throughout the world". DJs such as Frankie Knuckles, Marshall Jefferson, Paul Johnson and Mickey Oliver celebrated the proclamation at the Summer Dance Series, an event organized by Chicago's Department of Cultural Affairs.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): In 2005, what anniversary was Oliver music celebrating?
unanswerable