Facts that change
Core about 5 min
| Fact | Value | As of | Source |
|---|---|---|---|
| Nifty 50 F&O lot size (for journal questions on expiry) | 65 | 2026-11-05 | NSE F&O UDiFF bhavcopy, nsearchives.nseindia.com |
| Nifty weekly option expiry day | Tuesday (previous trading day if a holiday); since 1 Sep 2025 | 2026-11-06 | Business Standard |
| Most recent NBER US business-cycle peak / trough | Feb 2020 / Apr 2020; no later peak listed | 2026-11-06 | NBER |
| US real GDP growth, 2023 (annual average) | 2.5% (BEA advance estimate; may since be revised) | Jan 2024 release | BEA, Q4 and year 2023 advance estimate |
| India VIX methodology | Nifty-option-based, 30-day, CBOE-style (not re-verified here) | 2026-11-06 | NSE India VIX documents, nseindia.com |
arch / statsmodels versions used by the tests |
8.0.0 / 0.15.0 | 2026-11-06 | local uv environment |
hmmlearn maintenance status |
"limited-maintenance mode" | 2026-11-06 | project README, https://github.com/hmmlearn/hmmlearn |