IPv6 share of fetched URLs (IPv6 / (IPv4 + IPv6)) per crawl epoch, from Nutch job logs. Zeros for CC-MAIN-2024-10 through 2024-46 reflect absence of ip_address_version counters before Nutch instrumentation was added.
CC-MAIN-2026-12: OkHttp Happy Eyeballs enabled — IPv6-capable hosts now preferentially reached over IPv6