OPEN's biggest one-day moves since 2021, and what happened next
Describes the past; not a signal. Pre-licensed data — internal estimates, to be re-verified after our licensed data rebuild.
Close-to-close daily changes from 5 Apr 2021 to 6 Nov 2026 (1407 sessions). Later changes are measured from the close on the day of the move.
Biggest one-day falls
Of these 9, 6 were higher 21 sessions later · n = 9 · could be chance.
| Date | One-day change | After 5 sessions | After 21 sessions | After 63 sessions |
|---|---|---|---|---|
| 4 Aug 2023 | -26.3% | -3.1% | +6.9% | -37.9% |
| 6 Aug 2025 | -24.6% | +27.4% | +250.0% | +264.2% |
| 25 Feb 2022 | -23.1% | -19.9% | +6.0% | -22.7% |
| 9 May 2025 | -23.1% | +16.8% | -10.1% | +244.3% |
| 6 Nov 2026 | -21.8% | pending | pending | pending |
| 23 Jul 2025 | -20.5% | -9.6% | +57.2% | +203.9% |
| 9 Jun 2025 | -16.8% | -1.8% | +56.0% | +979.5% |
| 16 Jun 2022 | -15.8% | +31.0% | +28.0% | -6.0% |
| 23 Sep 2025 | -15.4% | +12.4% | -3.8% | -9.4% |
| 23 Apr 2025 | -15.2% | -9.9% | -19.1% | +187.8% |
Biggest one-day rises
Of these 10, 6 were higher 21 sessions later · n = 10 · could be chance.
| Date | One-day change | After 5 sessions | After 21 sessions | After 63 sessions |
|---|---|---|---|---|
| 11 Sep 2025 | +79.5% | -5.5% | -28.0% | -33.5% |
| 16 Jul 2025 | +43.3% | +53.7% | +104.0% | +412.8% |
| 21 Jul 2025 | +42.7% | -27.1% | +12.8% | +123.1% |
| 22 Aug 2025 | +39.2% | -11.2% | +41.5% | +23.0% |
| 18 Jul 2025 | +36.4% | +12.9% | +68.0% | +216.0% |
| 5 May 2023 | +32.6% | +8.9% | +37.4% | +92.2% |
| 10 Nov 2022 | +26.5% | -2.1% | -24.1% | +5.2% |
| 14 Aug 2025 | +25.6% | +18.4% | +212.3% | +208.2% |
| 7 May 2025 | +24.4% | -14.0% | -22.0% | +112.2% |
| 12 Aug 2021 | +24.0% | -17.0% | -1.2% | +8.6% |