As of 2010[update], Seattle has one major daily newspaper, The Seattle Times. The Seattle Post-Intelligencer, known as the P-I, published a daily newspaper from 1863 to March 17, 2009, before switching to a strictly on-line publication. There is also the Seattle Daily Journal of Commerce, and the University of Washington publishes The Daily, a student-run publication, when school is in session. The most prominent weeklies are the Seattle Weekly and The Stranger; both consider themselves "alternative" papers. The weekly LGBT newspaper is the Seattle Gay News. Real Change is a weekly street newspaper that is sold mainly by homeless persons as an alternative to panhandling. There are also several ethnic newspapers, including the The Facts, Northwest Asian Weekly and the International Examiner, and numerous neighborhood newspapers.

Answer this question, if possible (if impossible, reply "unanswerable"): In what year did the Seattle Post-Intelligencer  first publish?
1863