Two weeks after Google introduced AI Overviews (AIOs), early data reveals their impact on organic traffic, especially in the health vertical. AIOs can reduce organic traffic, particularly for queries seeking quick answers, though some AIOs may drive traffic to cited sites.
When AIOs Appear
Using ZipTie to analyze 1,675 health-related queries, AIOs appeared in 42% of cases, significantly higher than in ecommerce. Longer queries are more likely to trigger AIOs, and they often appear with other SERP features like People Also Ask (PAA) and Featured Snippets (FS). No strong correlation was found with keyword difficulty or search volume.
Sites Cited in AIOs
The dataset showed 704 AIOs citing 4,493 sites, averaging 6.3 links per AIO. There is a strong correlation (0.917) between sites in the top 10 organic results and those cited in AIOs. Surprisingly, platforms like Reddit and Quora contributed minimally to citations. No strong relationship was found between AIO citations and a site's organic traffic, backlinks, or ranking keywords.
Traffic Impact of AIOs
Comparing organic clicks from Search Console for a domain across 1,675 keywords, a strong negative correlation (-0.61) was found between cited URLs and traffic change, indicating fewer clicks to cited URLs. The domain received -8.9% fewer clicks when cited in AIOs. However, results vary by user intent, with some AIOs potentially driving more traffic based on the complexity of the query.
When AIOs appear without citing a site, there is an average loss of -2.8% in organic traffic. This suggests users might still click on organic results, but more data is needed to confirm this.
Caveats
AIOs can change frequently, and Google has pulled back many AIOs due to reports of misleading information. The current dataset of 1,675 queries is a good start, but more extensive data is needed for robust conclusions.
Conclusion
Strong SEO performance appears to be the best way to appear in AIOs, though Google also cites less well-performing URLs. AI Overviews significantly impact Google's search ecosystem and could either prove the value of AI in products or expose its limitations.