The rise of mobile is contributing to declining ad viewability levels, with around £750m per year wasted on non-viewable ads as a result.

According to ad attention solutions provider Meetrics, the proportion of banner ads that met minimum viewability guidelines dropped from 49 per cent to 47 per cent in Q1 2017 – the lowest level for nine months.

“Declining viewability is partly driven by mobile now accounting for over half of display ad spend but tending to have lower viewability rates than desktop for various reasons,” said Anant Joshi, commercial director UK & Ireland at Meetrics. “Obviously, the smaller screen size can mean more page scrolling and, thus, more chance of ads being missed lower down a page, plus slower network connection speeds can cause ad loading delays. There’s also the legacy issue of desktop ads served on mobile which don’t format properly, despite the use of responsive design.”

According to Joshi, declining viewability can also be attributed to the increasing amount of time being spent in-app – where ads are more likely to be at the bottom of the page so won’t always get seen.

He also added that a similar decline in viewability can be seen elsewhere across. Germany saw a three per cent drop to an all-time low of 55 per cent viewability, while Austria dropped one per cent to 67. However, France rose three points to 60 per cent. All of the above maintaining higher viewability levels than the UK though.

“Unfortunately, we’re still seeing a lot of talk but not the required intense effort to increase viewability and improve campaign ROI. This needs to change,” Joshi concluded.