Programmatic buying and selling accounted for 20 per cent of overall internet advertising revenues in the US last year, according to a study by the IAB and PwC.

Programmatic revenues stood at $10.1bn (£6.5bn) in 2014, with 80 per cent of that figure coming from desktop display banner ads. The report doesnt specifically break out mobile, but it makes up some proportion of the remaining 20 per cent.

Of the total programmatic revenues, 55 per cent went to ad tech companies, and 45 per cent to publishers.

“Sizing the programmatic market has proven both challenging and illuminating, as we learned more about how that sector moves ads and money,” said Sherrill Mane, SVP research, analytics and measurement at IAB US. “Once we garner deeper understanding of how things work and where standard definitions and best practices are needed, we will also gain insights into where greater opportunities exist for publishers and advertisers to capitalize on programmatic channels.”

Alongside the study, IAB has also launched the Programmatic Fee Transparency project, a working group set up to develop a set of best practices involving fee disclosures.