HubSpot 2015 (n=13,500+): companies posting 16+ blog posts/month got "almost 3.5× more inbound traffic" — dated but still cited

Claim: HubSpot's 2015 study of 13,500+ customers found that "companies that published 16+ blog posts per month got almost 3.5× more inbound traffic than companies that published between 0-4 monthly posts."

Source: HubSpot 2015 inbound study (widely re-circulated since).

Confidence: Industry-consensus on direction; dated dataset — almost certainly does not survive 2024-2026 Google E-E-A-T updates intact in magnitude. Use as steel-man material, not current benchmark.

Companion 2025 data point: Stratabeat's B2B SaaS data — "websites that published 9+ blog posts per month saw a 20.1% increase in monthly organic traffic." Same direction, single-source, more recent.

The honest reading: volume-correlation data points one direction; the AI-citation and trust dimensions point the other. Research-first competes on the trust/citation axis. Both can be true: a research-first SMB writing 1 article every 2-4 weeks captures different value than a content factory writing 16+/month.