Revenue lost from ad blocking estimated at $21.8 billion

The number of people using ad blocking software has grown by 41% globally over the past year, and the software is expected to hit ad revenues by more than $21.8 billion in 2015.

A report from PageFair and Adobe found there were 45 million average monthly active users of ad blocking software in the second quarter of 2015 in the US.

The use of ad blockers globally grew by 41% in the second quarter of the year. The Cost of Ad Blocking study said there were 198 million monthly active users for the major browser extensions that block ads.

The research also said predicted that ad blocking will cost £26.8 billion $41.4 billion globally by 2016.

The study added that sites aimed at "young, technically savvy, or more male audiences" are the most affected by ad blockers.

Gaming sites took a 26.5% share of the global ad blocking market in the second quarter of 2015, whereas government and legal sites only had a 2.5% share.

Sean Blanchfield, the co-founder and chief executive at PageFair, said, "It is tragic that ad block users are inadvertently inflicting multi-billion dollar losses on the very websites they most enjoy.

"With ad blocking going mobile, there’s an eminent threat that the business model that has supported the open web for two decades is going to collapse."

In June, Apple revealed that ad blocking software could be available in the next major operating software upgrade of the iPhone.