Global advertising spend in 2013

Roughly half way through the year, estimates seem to draw a coherent picture about the size and the various components of the total 2013 advertising spending in the world. Total spend is some half a trillion dollars. About a third of this comes from the US and most of the growth is from the emerging economies.
More interesting is the evolution of the composition of advertising spend. TV still dominates and the classical media are relatively stable. Only print declines, albeit slowly at -4%. What is notable - although not that surprising - is  the explosive growth of digital advertising spend and, in particular, mobile and social-media ad spend. Search, video and classical digital (banner) advertising also grows at a fast pace (10-20%). At this rate of change, it is reasonable to assume that digital media will represent 25% of total spend by the end of next year.