According to Billboard.com and Nielsen SoundScan, digital albums were primarily the only music unit to witness a somewhat modest increase compared to sales in 2009. 86.3 million digital albums were sold in 2010 as opposed to 76.4 million sold in 2009, a 13 percent increase.
Sales of physical albums (CD’s) dropped by 20 percent, a number that has steadily decreased in the past four years.
Overall music unit sales (albums, digital tracks, and music videos) in 2010 totaled 1.51 billion, a 2.4 percent decrease compared to the year prior.
As expected the lack of album sales are a result of illegal downloads on peer-to-peer networks and also the decreasing presence of music shops.
SoundScan was created in 1991 and has been used to calculate various Billboard music charts.