Carat has published its first forecast for worldwide ad spend in 2015, predicting 5 per cent growth year-on-year driven by programmatic buying and mobile.

This year, global ad spend is expected to grow 4.8 per cent to $551bn (£331bn), an upward revision on Carats previous estimate from September. This will be driven by digital, which includes mobile, video and social, predicted to grow by 15.5 per cent.

Digital is the only sector predicted to increase its media share in 2014 and will accelerate into next year too. It already represents the number one media type in the UK, Denmark, Norway and Sweden, and its growth looks to be at the expense of both newspapers and magazines.

“The choice for advertisers and brands is increasing year on year,” said William Rusack, head of mobile at Carat. ” There are more opportunities and a shift away from the banner and button era to native ads that are integrated into mobile sites and apps is helping mobile advertising take a bigger share of the overall ad spend. Digital growth accounts for three times total growth and the seismic trends within digital are causing a convergent media revolution.”

Actual growth in 2013 reached 3.3 per cent so 2014 and 2015 estimates indicate that the global ad market is clearly on the road to recovery. Carats forecast for 2015 combines 2014 predictions along with actual figures for 2013.