Doc Searls Weblog

The answer is, we don’t know. Also, we may never know, because—

• It’s too hard to measure (especially if you’re talking about the entire Net).
• Too so much of the usage is in mobile devices of too many different kinds.
• The browser makers are approaching ad blocking and tracking protection in different and new ways that change frequently, and the same goes for ad-blocking and tracking-protecting extensions and add-ons. One of them (Adblock Plus) is actually in the advertising business (which Wikipedia politely calls ad filtering) in the sense that they sell safe package for paying advertisers.
• Some of the most easily sourced measures are surveys, yet what people say and what they do can be very different things.
• Some of the most widely cited findings are from sources with conflicted interests (for example, selling anti-ad-blocking services), or which aggregate multiple sources that aren’t revealed when cited.
• Actors good and bad in the ecosystem that ad blocking addresses also contribute to the fudge.

But let’s explore a bit anyway, working with what we’ve got, flawed though much of it may be. If you’re a tl;dr kind of reader, jump down to the conclusions at the end.

Part 1: ClarityRay and Pagefair

Between 2012 and 2017, the most widely cited ad blocking reports were by ClarityRay and PageFair, in that order. There are no links to ClarityRay’s 2012 report, which I cited here in 2013. PageFair links to their 2015, 2016 (mobile) and 2017 reports are still live. The company also said last November that it was at work on another report. This was after PageFair was acquired by Blockthrough (“the leading adblock recovery program”). A PageFair blog post explains it.

I placed a lot of trust in PageFair’s work, mostly because I respected Dr. Johnny Ryan (@JohnnyRyan), who left PageFair for Brave in 2018. I also like what I know about Matthew Cortland, who was also at PageFair, and may still be. Far as I know, he hasn’t written anything about ad blocking research (but maybe I’ve missed it) since 2017.

Here are the main findings from PageFair’s 2017 report:

• 615 million devices now use adblock
• 11% of the global internet population is blocking ads on the web

Part 2: GlobalWebIndex

In January 2016, GlobalWebIndex said “37% of mobile users … say they’ve blocked ads on their mobile within the last month.” I put that together with Statista’s 2017 claim that there were then more than 4.6 billion mobile phone users in the world, which suggested that 1.7 billion people were blocking ads by that time.

Now GlobalWebIndex‘s Global Ad-Blocking Behavior report says 47% of us are blocking ads now. It also says, “As a younger and more engaged audience, ad-blockers also are much more likely to be paying subscribers and consumers. Ad-free premium services are especially attractive.” Which is pretty close to Don Marti‘s long-standing claim that readers who protect their privacy are more valuable than readers who don’t.

To get a total ad blocking population from that 47%, one possible source to cite is Internet World Stats:

Note that Internet World Stats appears to be a product of the Miniwatts Marketing Group, whose website is currently a blank WordPress placeholder. But, to be modest about it, their number is lower than Statista’s from 2016: “In 2019 the number of mobile phone users is forecast to reach 4.68 billion.” So let’s run with the lower one, at least for now.

Okay, so if 47% of us are using ad blockers, and Internet World Stats says there were 4,312,982,270 Internet users by the end of last year (that’s mighty precise!), the combined numbers suggest that more than 2,027,101,667 people are now blocking ads worldwide. So, we might generalize, more than two billion people are blocking ads today. Hence the headline above.

Perspective: back in 2015, we were already calling ad blocking The biggest boycott in human history. And that was when the number was just “approaching 200 million.”

More interesting to me is GlobalWebIndex’s breakouts of listed reasons why the people surveyed blocked ads. Three in particular stand out:

• Ads contain viruses or bugs, 38%
• Ads might compromise my online privacy, 26%
• Stop ads being personalized, 22%

The problem here, as I said in the list up top, is that these are measured behaviors. They are sympathies. But they’re still significant, because sympathies sell. That means there are markets here. Opportunities to align incentives.

Part 3: Ad Fraud Researcher

I rely a great deal on Dr. Augustine Fou (@acfou), aka Independent Ad Fraud Researcher, to think and work more deeply and knowingly than I’ve done so far here (or may ever do).

Looking at Part 2 above (in an earlier version of this post), he tweeted, “I dispute these findings. ASKING people if they used an ad blocker in the past month is COMPLETELY inaccurate and inconsistent with people who ACTUALLY USE ad blockers regularly.” Also, “Source: GlobalWebIndex Q3 2018 Base: 93,803 internet users aged 16-64, among which were 42,078 respondents who have used an ad-blocker in the past month”. Then, “Are you going to take numbers extrapolated from 42,078 respondents and extrapolate that to the entire world? that would NOT be OK.” And, “Desktop ad blocking in the U.S. measured directly on sites which humans visit is in the 8 – 19% range. Bots must also be scrubbed because bots do not block ads and will skew ad blocking rates lower, if not removed.”

On that last tweet he points to his own research, published this month.There is lots of data in there, all of it interesting and unbiased. Then he adds, “your point about this being the ‘biggest boycott in human history’ is still valid. But the numbers from that ad blocking study should not be used.”

Part 4: Comscore

Among the many helpful tweets in response to the first draft of this post was this one by Zubair Shafiq (@zubair_shafiq), Assistant Professor of Computer Science at the University of Iowa, where he researches computer networks, security, and privacy. His tweet points to Ad Blockers: Global Prevalence and Impact, by Matthew Malloy, Mark McNamara, Aaron Cahn and Paul Barford, from 2016. Here is one chart among many in the report:

The jive in the Geo row is explained at that link. A degree in statistics will help.

Part 5: Statista

Statista seems serious, but Ad blocking user penetration rate in the United States from 2014 to 2020 is behind a paywall. Still, they do expose this hunk of text: “The statistic presents data on ad blocking user penetration rate in the United States from 2014 to 2020. It was found that 25.2 percent of U.S. internet users blocked ads on their connected devices in 2018. This figure is projected to grow to 27.5 percent in 2020.”

Provisional Conclusions

1. The number is huge, but we don’t know how huge.
2. Express doubt about any one large conclusion. Augustine Fou cautions me (and all of us) to look at where the data comes from, why it’s used, and how. In the case of Statista, for example, the data is aggregated from other sources. They don’t do the research themselves. It’s also almost too easy to copy and paste (as I’ve done here) images that might themselves be misleading. The landmark book on misleading statistics—no less relevant today than when it was written in 1954 (and perhaps more relevant than ever)—is How to Lie With Statistics.
3. Everything is changing. For example, browsers are starting to obsolesce the roles played by ad blocking and tracking protection extensions and add-ons. Brave is the early leader, IMHO. Safari, Firefox and even Chrome are all making moves in this direction. Also check out Ghostery’s Cliqz. For some perspective on how long this is taking, take a look at what I was calling for way back in 2015.
4. Still, the market is sending a massive message. And that’s what fully matters. The message is this: advertising online has come to have massively negative value.

Ad blocking and tracking protection are legitimate and eloquent messages from demand to supply. By fighting that message, marketing is crapping on most obvious and gigantic clue it has ever seen. And the supply side of the market isn’t just marketers selling stuff. It’s developers who need to start working for the hundreds of millions of customers who have proven their value by using these tools.