This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Passage: 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.
When was House Unity Day in Jefferson?