Last.fm released figures today that it says prove full song streams have a direct impact on sales. Since adding full streams in January, Last.fm reports that overall purchases through its partnership with Amazon increased 119%. The site also noted an increase an overall visitors, but said that existing users fueled a significant part of the sales jump, as they purchased 66% more music once full albums had been added. Though Last.fm also has partnerships with iTunes and 7Digital, no figures were released for those outlets.

The Amazon.com information, however, is enough for Martin Stiksel, the co-founder of Last.fm. He says that this demonstrates that giving users free access to streaming songs encourages music purchasing:

 "In just over two months it's become clear that people will buy CDs and downloads if they get access to the kind of service we offer.  No one else can give music fans this amount of music for free — but more importantly also drive their discovery, as we do through our unique recommendation engine. That’s why people are sticking around on Last.fm — minutes spent on site are up 118% month-on-month — and discovering new music to listen to and buy."

Last.fm was founded in 2002, and claims over twenty-one million active users based in more than two hundred countries. [Hypebot]