We reported yesterday on Billboard’s decision to add data from six streaming music services to its Hot 100 chart. But it turns out there’s another dimension to the change: a brand new ‘On-Demand Songs’ chart produced using just this data, working with Nielsen and NARM’s Digitalmusic.org site. The data is coming from Mog, Muve Music, Rdio, Rhapsody, Slacker and Spotify, although Billboard says Zune and Sony Music Unlimited should be added soon. There’s plenty of data to go on: Nielsen has apparently tracked 4.5bn song streams in 2012 so far. “As our relationships have grown to include most of the largest music streaming services in the business, we have measured an all-time weekly high of more than 625 million total streams in the past week alone,” says Nielsen’s Chris Muratore. Fun and Janelle Monae’s ‘We Are Young’ tops the first On-Demand Songs chart with 1.1m streams – it’s also currently topping the Hot 100 list.