The cover of Adele's blockbuster '21' album.

Adele ’21′ continues on the fast track to become the first album since 2004 to achieve diamond status. In fact, the LP has surpassed yet another major marker in the US as it has officially been certified 9x platinum by the RIAA for shipments exceeding 9 million units.

With over 8.74 million copies sold at retail outlets, ’21′ is the best-selling album in the US since Usher’s ‘Confessions‘ LP in the 2004. Additionally, the record has yet to leave the top 10 of the Billboard 200 and has thus far logged 23 nonconsecutive weeks atop the chart as the longest-running #1 album since Prince’s ‘Purple Rain’ in 1985.

’21′ has also generated the top-selling digital single by a solo artist in the US. ‘Rolling in the Deep’ has sold over 7 million downloads in just 67 weeks and is the second most downloaded track in US history after the Black Eyed Peas’ ‘I Gotta Feeling’, which has sold 7.89 million million downloads since 2009.

Adele has thus far scored 3 #1 singles on the Billboard Hot 100 from ’21′ – ‘Rolling in the Deep’, ‘Someone like You’ and ‘Set Fire to the Rain’. Her latest release, ‘Rumour Has It’, recently climbed to a new peak on the chart by ranking at #20.

Watch Adele perform ‘Rumour Has It’ below:

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