The study, which is based on data collated from seven leading verification companies, found that average display viewability (percentage of ads that were on view across all devices) was highest in Sweden (52%) and worst in Russia (32%), which performed 10 points worse than the second-lowest market (China).
These numbers, which do not include Facebook or YouTube, are based on data from the first half of 2017 and uses Media Ratings Council definitions to define viewability – 50% of surface area in view for one second for display and 50% for two seconds for video.
The UK's average display viewability was 47% while the US did slightly better at 49%. Indonesia ranked third out of all the markets with an average 51%.
In terms of video, however, Indonesia ranked at the absolute bottom with 35% viewability and Austria led the group with 72%.
The UK and the US were once again middling performers in the video viewability rankings with an average rate of 56% and 60% respectively.
Overall, average viewability from MRC-accredited companies for display is just under 50% with video averaging 60%, with at least four out of 10 impressions unviewed.
Video viewability improves
When comparing results for the first half of 2017 against the second half of 2016, the report found marginal improvement (0.6%) in performance for display across the 20 markets. Video, on the other hand, was up four percentage points.
Norway led the charge with a rise of 16 percentage points. The UK only improved about a percentage point in and the US around four percentage points.
The improvement in video performance is believed to be down to the pivot to premium sites among advertisers and a gradual removal of long-tail, less effective publishers.
"Viewability is expected to be lower in newsfeed environments, linked to the speed users scroll through content, so a true census of the market would probably find lower global viewability levels than those identified by the WFA’s data," Matt Green, global lead for media and digital marketing at the WFA. "Independent, third-party measurement is critically important to advertisers and we encourage all platforms to accept third-party scripts and to adopt industry standards."
The WFA is also working alongside IAB Europe, EACA, Jicwebs in the UK, AGOF in Germany and Digital Ad Trust in France to improve viewability standards in Europe and beyond.
There are also efforts being made in individual markets to raise standards so that brands can trade against a higher viewability standard as a norm. In the UK, for example, ISBA has announced plans to give brands the ability to buy display at 100% in-view.
"Global viewability levels associated with the MRC’s definition of 50% of surface area are not advancing particularly fast but we expect this to change as more global marketers and national advertiser associations specify a higher basic viewability threshold," Green said. "Ultimately, brands should be able to trade on whatever viewability level delivers the required outcome at the right cost."
One of the challenges for marketers is that different verification companies can produce very different average viewability rates for each market.
For example, across six vendors that cover the Australian market, the lowest viewability rating was 26% and the highest at 88%, resulting in an average (in this report) of 50%.
The greatest divergence for video was seen in the Netherlands where the range across four vendors was 57 percentage points, with a low of 11% and a high of 68% in-view impressions.
Other markets showed much closer alignment between vendors and was as little as four percentage points for US video viewability.
"A divergence between vendors for viewability does not mean that one is right and one wrong but is a reflection of the fact that each company is working with a different set of clients, each deploying its own choice of formats and placements," Green said.
However, he added, it’s worth drawing attention to the fact that there are still variances in technique and technology provided by verification companies.
"Marketers need to assess the way viewability companies measure, paying particular attention to how this works in mobile and in-app environments," Green, said.