With the record industry still struggling to move physical albums, pop star Katy Perry's hit single, "California Gurls," led the world in digital download sales with 4.4 million. According to figures released by Nielsen SoundScan, total album sales for the year were 12.8 percent below sales from the previous year, while digital album sales increased by 13 percent. Digital sales accounted for just over one-fourth of all album sales for the year, a new record. Only 13 albums sold a total of 1 million copies in 2010, an all-time low since SoundScan began tracking sales.
