The body's Digital Music Report 2012 - which takes into account 12-month sales to November 2011 - shows that the singer's Just The Way You Are sold 12.5 million units across the globe, whilst Mars' Grenade shifted 10.2 million in the year.
According to IFPI data*, the world's top-selling digital singles of 2011 were:
Bruno Mars - Just The Way You Are (12.5m)
Bruno Mars - Grenade (10.2m)
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