Longest stay by an album on a music chart

On 28 April 2012, Pink Floyd’s (UK) 1973 album The Dark Side of the Moon recorded its 802nd week (nearly 15-and-a-half years) on the US Billboard 200. Pink Floyd's eighth studio album, recorded at London's Abbey Road Studios, spent a solitary week at No.1 in April 1973 and, according to the Recording Industry Association of America (RIAA), has been certified for shipments of 15 million copies in the USA. The album has sold an estimated 50 million copies worldwide. Johnny’s Greatest Hits (1958) by Johnny Mathis (USA) is the runner-up with 490 weeks – 306 weeks (almost six years) shy of Pink Floyd’s mark.