NEW YORK: Fears of a so-called "mobilegeddon" following Google's change to its search algorithm in April appear unfounded but those sites that remain unoptimised for mobile have seen a definite loss of traffic according to a new report.

The Adobe Digital Index (ADI) Digital Advertising Report for the second quarter highlighted a 10% fall in organic traffic to sites with low mobile engagement.

"While there wasn't a precipitous drop among non-friendly sites, the effect is pronounced over the ten weeks after the event," Tamara Gaffney, principal at ADI, told

"Such continued loss of traffic suggests that immediate emphasis would have been placed on paid search as a quick way to recover traffic," she added. "But that strategy is not necessarily sustainable."

ADI's report indicated that these marketers were paying 16% more year-on year in terms of cost-per-click while the click-through rate had fallen 9%.

Google has come later to mobile than rival Facebook and has still not fully addressed its role as an advertising platform.

"There have been radical changes that Facebook has done and less radical changes Google has done," Gaffney said. "And consumers in the marketplace are feeling ads on Facebook are more relevant."

She was referring to Facebook's decision to halve the number of display ads on a page and to introduce ads within the newsfeed.

"Decreasing the number of ads on a page reduced the total number of impressions served, but the trade-off has been an increase in engagement," she explained, with CTRs almost doubling.

Google's less drastic approach, meanwhile, has resulted in a 3% decrease in consumer actions.

"They're starting to lose ground as a marketing vehicle," Gaffney said. "And part of the reason why is because they aren't getting as many clicks out of global display ads."

Data sourced from, Adobe Digital Index; additional content by Warc staff