Yellen – Social Media, Biotech overvalued

http://www.zerohedge.com/news/2014-07-15/yellens-irrational-exuberance-moment-arrives-she-pops-momo-biotech-social-media-bubb

Comment: Blah Blah Blah great, anyone who doesn’t know companies trading at 40 times revenues is insane is insane. However, who created this bubble?