Digital music sales declined for the first time in 2013 since the iTunes Store opened a decade before, according to new data from Nielsen SoundScan. Billboard reports that sales of tracks declined 5.7 percent, to 1.34 billion units, while album sales fell 0.1 percent, to 117.6 million. The chief culprit, according to executives interviewed by Billboard: streaming services like Spotify and Pandora.

At around $10 a month for unlimited listening, the streaming services are proving to be an attractive alternative to albums that cost $10 apiece. The good news for record labels: so far, revenue from streaming services has offset the decline in sales. And digital sales are falling much more slowly than sales of physical media — CD sales fell 14.5 percent last year.