From Billboard:
The total volume of the on-demand streaming marketplace has increased by 50 percent, as tracked by Billboard, in the past year, from around 274 million streams a week in Nov. 2013 to roughly 413 million weekly streams in Nov. 2014. YouTube and Spotify are the clear leaders in the space, with roughly more than 91 percent of the total volume of on-demand streams in any given week coming from these two services. Over the past year, Spotify has begun to take market share from YouTube for the overall streaming volume of top tracks.
Keep in mind, this is not a market share, but rather a look at shares of top-charting songs. With the exception of the overall volume numbers, the breakdowns and increases are calculated just from the top 50 most-played songs in each period.
In this breakdown, Spotify grows in shares over the year, from 22 percent to 33 percent, while YouTube drops from 66 percent to 58 percent of the total share. Comparing the two time-based graphs, a big spike appears in August, from the week when the official music videos for “Shake It Off” and “Anaconda” were released. Generally, YouTube is much more prone to drastic spikes in activity as consumers rush to the platform for big video debuts (“Anaconda” currently holds the Vevo record for 19.6 million global views in 24 hours).
