Hang Seng: a 3.3σ fall on 2 October 2026
Recorded 7 October 2026On 2 October 2026 Hang Seng fell 2.60% close to close, 3.3 times its typical daily move of 0.79% over the 20 sessions before it: larger than every one of the 63 sessions on record before it. 5 other instruments of the 146 measured that day moved 2σ or more.
The day
Daily closes, as recorded the night after
- Move
- −2.60%
- Size
- −3.3σ
- Typical day before it
- 0.79%
- Close
- 23,972.29
- Previous close, 30 September 2026
- 24,613.27
- Since, to 21 October 2026
- −1.34%
Hang Seng, the 30 sessions to 2 October 2026
Daily closes; the last point is the quake
Show values
| Point | HSI |
|---|---|
| 20 Aug 2026 | 25,698 |
| 21 Aug 2026 | 26,009 |
| 24 Aug 2026 | 25,517 |
| 25 Aug 2026 | 25,511 |
| 26 Aug 2026 | 25,653 |
| 27 Aug 2026 | 25,566 |
| 28 Aug 2026 | 25,585 |
| 31 Aug 2026 | 25,567 |
| 1 Sep 2026 | 25,330 |
| 2 Sep 2026 | 25,311 |
| 3 Sep 2026 | 25,213 |
| 4 Sep 2026 | 25,651 |
| 7 Sep 2026 | 25,413 |
| 8 Sep 2026 | 25,317 |
| 9 Sep 2026 | 25,275 |
| 10 Sep 2026 | 24,954 |
| 11 Sep 2026 | 24,806 |
| 14 Sep 2026 | 24,918 |
| 15 Sep 2026 | 24,667 |
| 16 Sep 2026 | 24,714 |
| 17 Sep 2026 | 24,604 |
| 18 Sep 2026 | 24,751 |
| 21 Sep 2026 | 25,043 |
| 22 Sep 2026 | 25,088 |
| 23 Sep 2026 | 24,834 |
| 24 Sep 2026 | 24,761 |
| 25 Sep 2026 | 24,510 |
| 28 Sep 2026 | 24,643 |
| 29 Sep 2026 | 24,524 |
| 30 Sep 2026 | 24,613 |
| 2 Oct 2026 | 23,972 |
The same day
Other quakes on 2 October 2026
| Instrument | Move | Size |
|---|---|---|
| Bovespa BVSP | +2.63% | +3.4σ |
How it is measured
The move is the close-to-close return; its size is that return divided by the standard deviation of Hang Seng's previous 20 daily returns. A quake is 3σ or more. This record was made the night after the day finished trading and has not been changed since. The live chart is on Hang Seng's page; the last few months of every market's daily moves are on the volatility terrain, and every quake on record is in the quake archive.