Digital ad spend is set to grow to $42.26bn this year, and will account for 24.7 per cent of total media ad spending this year, according to eMarketer's latest estimates on US ad spending.
The research found that digital is set to grow from $36.80 billion in 2012; with mobile to play a bit part in this, as it is expected that mobile spend will grow by 95 per cent.
In total, it is suggested that mobile will account for a fifth (20.1 per cent) of all digital ad spending, and five per cent of total media ad spending.
This year, eMarketer expects 51.5 per cent of all spending on mobile ads to go toward search, compared to 44.8 per cent for display ads, including banners, video and other formats.
eMarketer's latest forecast for digital ad spending anticipates 14.9 per cent growth for the year, which it suggests is set to continue falling through 2017, when spending will rise 7.1 per cent to reach $61.35bn.