Chicago IX: Chicago's Greatest Hits

Chicago IX: Chicago's Greatest Hits is the first greatest hits album, and ninth album overall, by the American band Chicago and was released in 1975 by Columbia Records in both stereo (PC 33900) and SQ quadraphonic (PCQ 33900) versions. Including all of Chicago's biggest hits to date, this set stretches from their 1969 debut, Chicago Transit Authority, to 1974's Chicago VII. Chicago VIII and its hits, having only come out just months earlier, were considered too recent to anthologize, while Chicago III's material was overlooked for inclusion due to its lack of top-selling singles. Chicago IX proved to be an enormous success upon its release. It reached #1 in the US and remained on the Billboard 200 for a total of 72 weeks. It has since been certified quadruple platinum by the RIAA, signifying sales of over five million copies. Even though 2002's The Very Best of Chicago: Only the Beginning superseded it, Chicago IX was also reissued by Rhino Records, Chicago's current distributor. The album did not chart in the UK. This album was mixed and released in both stereo and quadraphonic.