Apple’s growing slice of the music business – in pie charts by Philip Elmer-DeWitt @FortuneMagazine August 18, 2009, 6:53 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons Source: NPD Group The NPD Group on Tuesday issued what at first appears to be a pair of contradictory facts: Apple AAPL now controls the largest share of the music business, its iTunes Store accounting for 25% of unit sales in the first half of 2009, up from 14% in 2007. Compact discs are still the most popular format for paid music, accounting for 65% of unit sales. How can this be? The trick is that Apple controls the lion’s share — 69% — of paid downloads, whereas CD sales are spread out among many players, chief among them Wal-Mart WMT , Best Buy BBY , Amazon AMZN and Target TGT . To see better how this works, let’s put the data into pie charts: Source: NPD Group Source: NPD Group Source: NPD Group Not covered in the NPD report, of course, is music piracy, which according to a recent U.K. report accounts for roughly 18% of music downloads — which would put it ahead of Amazon but well behind iTunes.