NEW YORK: Mobile claimed more than half of digital advertising expenditure in the US last year, according to new figures from the Interactive Advertising Bureau (IAB).

Research by the trade body, conducted in partnership with auditing and consulting group PricewaterhouseCoopers (PwC), found that total interactive spend rose by 22% year on year in 2016, reaching a record high of $72.5bn.

Within this, mobile logged a 77% surge in revenue to $36.6bn over the 12 months as a whole, compared with $20.7bn in 2015.

Randall Rothenberg, President/CEO of IAB, suggested this result offered compelling evidence that brand custodians are now comfortable with making this channel a central part of their plans.

"Mobile fueled the internet economy in 2016, with advertisers showing their confidence in digital to achieve their marketing goals," he said in a statement.

"This increasing commitment is a reflection of brands' ongoing marketing shift from 'mobile-first' to 'mobile-only' in order to keep pace with today's on-the-go consumers."

One contributor to the growth of mobile was video, where spend levels climbed by 145% on an annual basis, reaching almost $4.2bn. Digital video across all channels was worth $9.1bn, up 53% on the previous year.

Mobile banners also registered a 51% lift to $13.9bn, while paid-for search ads on wireless devices expanded by 91% to $17.2bn. Search revenues across the entire digital ecosystem improved by a more modest 19%, to $35bn.

Elsewhere, the analysis showed that social media attracted $16.3bn in spend last year, representing a 50% increase from 2015 – and placing platforms like Facebook at the heart of the rapidly evolving digital ad market.

"Mobile, social, video, and programmatic trends combine to redefine the digital landscape, providing unprecedented access for advertisers to reach consumers," said David Silverman, a partner at PwC US.

One new expenditure category broken out by the IAB and PwC was digital audio, which secured $1.1bn in revenue last year. Some 81% of this spend was drawn from mobile, and Silverman predicted further growth in this area going forwards.

"Digital audio generating $1.1bn in 2016 speaks to the continued evolution of new formats that enable marketers to find audiences at home, behind their desks, or wherever they are," he said.

Data sourced from IAB; additional content by WARC staff