Apple remains in control of digital music sales in the US, but has lost some ground in the past few years, according to a new NPD Group report. The company currently holds a 63 percent marketshare with iTunes, down from 66 percent in 2010. Amazon has meanwhile established itself as a major player, now at 22 percent of the market versus 13 percent in 2010. The companies are however competing for a static number of music buyers, since the number of Americans that have bought at least one song has remained at roughly 44 million annually for the past three years.
