US online display advertising will grow from $19.8 billion this year to $37.6 billion in 2019 — a 13.7% compound annual growth rate (CAGR), according to Forrester’s latest five-year forecast. In Europe, online display ads will grow at 10.3% CAGR over the next five years.
Comparatively, the offline market in the US will increase at only an average annual rate of 1% and will reach $239 billion in 2019.
The online ad market will see high growth from three key sectors of the display market: programmatic exchange-based trading, online video, and mobile display.
According to the forecast, exchange-based trading will make up 30.2% of total display impressions by 2019, nearly double the 2012 levels. Further, Forrester predicts the addition of premium and high-value inventory to ad exchanges to further drive up exchange-traded average CPMs — expected to hit $4.34 in 2019, up from $3.31 this year. By 2019, 71.4% of display ad spend will be sold based on performance, 26.6% based on impressions, and 2% will be sold on a sponsorship basis.
Video advertising on the PC will grow by 21% annually until 2019, contributing to 54.6% of total PC online display ad revenue. And on mobile, video advertising will grow by 36.9% annually — as marketers look to reach customers where they increasingly spend their time online.
Comparatively, mobile display ads will grow at a 24.5% CAGR over the next five years, making up 38.6% of total online display advertising in 2019, up from 24.4% this year.

Learn more about the US and EU forecasts on the Marketing Leadership blog.