Research
Performance marketing, with sources.
22 cited statistics on Google Ads, AI search, SEO/AEO, and regulated-vertical advertising. Each number links to the primary source. Built to be quoted.
AI Search
AI Overviews appearance rate on US Google queries (study period 2025)
~50% of queries surveyed showed an AI summary
Click-through rate drop on search results when an AI Overview is present
Users click only 8% of result links when an AI summary appears, vs 15% when none does
Perplexity disclosed monthly query volume
780 million queries in May 2025, growing
Princeton GEO study — citation-rate lift from citing authoritative sources
+40% LLM citation rate when external sources are present in content
Princeton GEO study — citation-rate lift from adding statistics with sources
+37% LLM citation rate when statistics with attributions are present
Princeton GEO study — citation-rate lift from expert quotations
+30% LLM citation rate when named-expert quotes are present
Princeton GEO study — keyword-stuffing penalty in LLM citation systems
−10% LLM citation rate when content uses keyword stuffing
Paid Media
Google Ads Smart Bidding minimum conversions before reliable optimization
30+ conversions per month per campaign (Target CPA); 50+ for Target ROAS
Smart Bidding learning-phase duration after major bid/budget/goal changes
7-14 days of volatile performance before re-stabilization
GCLID parameter lifespan for offline-conversion imports
90 days from click — uploads against expired GCLIDs are silently dropped
Customer Match minimum list size before audience becomes targetable
1,000 matched users (below threshold, audience is inactive)
Quality Score's auction-level impact on CPC
A 1-point Quality Score lift typically reduces CPC by 10-15% on the affected keyword
SEO & AEO
Average position threshold for inclusion in Google AI Overview citations
Typically requires top-5 organic rank for the underlying query
E-E-A-T fourth E ('Experience') added to Search Quality Rater Guidelines
December 2022 — Google added Experience as a first-party-knowledge signal
Core Web Vitals metrics used by Google's Page Experience signal
LCP (Largest Contentful Paint), INP (Interaction to Next Paint), CLS (Cumulative Layout Shift)
Knowledge Graph entity consolidation timeline for new entities
Typically 2-6 months for first appearance; faster with 3+ independent third-party citations
CRO
Mobile share of typical Google Ads traffic in 2026
65-75% mobile traffic across most accounts
Page load speed threshold beyond which Quality Score is capped
Pages with poor Core Web Vitals capped at Quality Score 5-6, regardless of ad copy
Regulation
Healthcare advertising — Google's personalized-health-condition targeting policy
Banned outright by Google's Ads Policy (no targeting based on inferred health conditions)
HIPAA Online Tracking guidance — what HHS OCR added in 2024
Required BAA coverage for tracking pixels on patient-portal pages and authenticated health content
LegitScript Healthcare Merchant Certification annual fee
Approximately $1,995/year + annual recertification
FDA OPDP — fair-balance requirement for prescription drug advertising
Every efficacy claim requires a corresponding risk presentation of comparable prominence
Citation policy: every statistic on this page is sourced to a primary publisher (Google, HHS, FDA, FTC, Pew Research, Princeton, regulator websites, or company-issued disclosures). If you find a stat here that's stale, outdated, or contradicted by a more recent primary source, email info@myleadsfactory.com and we'll correct it within 5 business days. We don't recycle other agencies' research summaries — only first-cited primary sources. See also our atomic-definition glossary.