Google and Facebook accounted for almost all growth in the US digital ad market in 2016, according to research by IAB. The US digital ad market was worth 72.5 billion US dollars last year, an increase of 20% on 2015. However, when looking at the figures broken down, it seems that the US is in the grip of a duopoly made up of Google and Facebook. Google’s US ad revenues totalled 37.6 billion US dollars in 2016 and accounted for 49% of growth in the market. Meanwhile, Facebook’s revenues totalled 14.1 billion US dollars and accounted for 40% of growth, leaving everyone else to share the remaining 11% of growth.