Annualised stdev of the trailing 21 session returns. COMPUTED BACKWARD, unlike UW's /volatility/realized which computes it FORWARD over ~20 sessions and is therefore not knowable on the date it is stamped with (DESIGN.md:139, the highest-priority provenance hazard in the document).
Last observed 2026-10-01, 1 day before 2026-10-02. The value is carried forward; it is not a reading for 2026-10-02.
The cross-section of every symbol at 2026-10-02 was stopped by its statement timeout. The XLK figures above are unaffected.
2025-09-19260 obs2026-10-01
