Someone finally ran the experiment: AI Overviews cut clicks 39.8% — and the clicks that vanished were not the worthless ones

What the study did, and what it found

The paper — The Impact of Google AI Overviews on Publisher Traffic and User Experience: Evidence from a Field Experiment (SSRN 6513059, posted April 3, 2026 and last revised June 17, 2026) — is the first causal test of the feature rather than an after-the-fact traffic correlation. As PPC Land and Search Engine Journal both report:

• Method: a custom Chrome extension randomly assigned participants to see Google's normal results page, a version with AI Overviews stripped out, or AI Mode — then passively tracked what they actually did. 1,065 desktop Chrome users in the US, 68,089 searches, data collected January 7 – February 10, 2026 (two weeks per participant). AI Overviews fired on roughly 41% of queries.
• Outbound organic clicks fell 39.8% when an AI Overview appeared. Zero-click searches rose 34.5%.
• Sponsored clicks did not meaningfully change. The ads kept getting clicked; the organic links did not.
• Users were not happier. Survey results were, in the authors' words, “precisely estimated nulls” on satisfaction, perceived information quality, and ease of finding information — no measurable improvement.
• The lost clicks were not the low-quality ones. This is the finding from the revised version. Google's standard defense is that AI Overviews only absorb visits that were worthless anyway. The researchers checked: about 4 in 10 same-tab clicks bounced back to the results page in both groups, roughly 18% of visits ended within 10 seconds in both groups, and time-on-site was statistically indistinguishable. They conclude the data is “at odds with the view that AIOs primarily eliminate low-engagement website visits.”

Why this matters even if you never cared about publisher traffic

It closes an argument. Until now, a business owner could reasonably tell themselves that the AI-search panic was an SEO-industry story about media companies, and that the traffic decline was confounded by a dozen other things. A randomized experiment removes the confounds: when the AI answers, the click does not happen — 40% of the time — and the people who didn't click were not the tire-kickers. The traffic that AI absorbs is real traffic.

The second-order consequence is the one that hits a local business. If four in ten organic clicks evaporate at the answer layer, then the answer itself — the paragraph the model writes, and the businesses it names inside that paragraph — becomes the thing that determines who gets the customer. It is no longer a preview of your website. It is a substitute for it. And you cannot see it happening: an AI that answers in-place and names your competitor generates no lost click in your analytics, no impression, no bounce. Nothing. Just a booking that goes somewhere else.

What to do with it

The measurement most businesses reach for — Google Search Console — was never built to answer this, and the new AI report doesn't fix it: it reports AI impressions only, not whether the model recommended you, and covers Google's surfaces only. The number that survives this study is a different one: how often does each engine name your business when a real buyer asks a real buying question? In our own measurements that number is low and unstable — across 152 local businesses the average was named in 46% of the answers its own customers would see, and in repeat runs of the same question on the same engine only 31% of recommended brands survived every repeat. The instability runs deeper than brand names: the core of domains cited by two or more engines replaced a third of its members in six days, and even the #1 cited domain in our four-engine corpus — reddit.com — owes nearly 70% of its citations to one engine.

The takeaway

Agarwal and Sen have made the click loss a fact rather than a vibe, and taken away the excuse that the missing visitors didn't matter. If 40% of the clicks are gone at the answer layer, the only defensible thing to track is the answer. A free 60-second check asks ChatGPT and Perplexity (the $79 audit adds Gemini and Claude, 25 questions sampled three times each) the questions your customers ask and reports how often each one recommends you — the metric that keeps working after the click stops.