The firm said that traditional impressions, click-through rates and branding metrics do not take into account instances when the advert may be served to a browser but not to the part fo the screen they are looking at.

Arno Hummerston, MD at GfK Nurago, explained: “Users may land on a page that includes your ad, but almost immediately scroll to a point where your ad is no longer visible – or only partially visible.”

As a result of this, GfK has launched DeliveryControl.dx which tracks browser activity, the position of an advert on a website, the user’s screen resolution and any scrolling. The firm uses Nurago’s tagging system to measure how visible the advert was and how long it was in view for.

Hummerston added: “Ultimately, the benefit is with the advertisers since they pay their ad agencies and marketers based on performance. DeliveryControl.dx gives them a far truer measurement of the actual time that their ad is getting – plus, it gives immediate reporting, which means that campaigns can be monitored and optimised as they are running.”