Costco: a 3.1σ rise on 14 October 2026
Recorded 16 October 2026On 14 October 2026 Costco rose 2.87% close to close, 3.1 times its typical daily move of 0.93% over the 20 sessions before it: its largest move since 25 September 2026. 29 other instruments of the 199 measured that day moved 2σ or more.
The day
Daily closes, as recorded the night after
- Move
- +2.87%
- Size
- +3.1σ
- Typical day before it
- 0.93%
- Close
- 982
- Previous close, 13 October 2026
- 954.63
- Since, to 21 October 2026
- +1.66%
Costco, the 30 sessions to 14 October 2026
Daily closes; the last point is the quake
Show values
| Point | COST |
|---|---|
| 1 Sep 2026 | 940 |
| 2 Sep 2026 | 928 |
| 3 Sep 2026 | 925 |
| 4 Sep 2026 | 916 |
| 8 Sep 2026 | 910 |
| 9 Sep 2026 | 903 |
| 10 Sep 2026 | 902 |
| 11 Sep 2026 | 905 |
| 14 Sep 2026 | 919 |
| 15 Sep 2026 | 901 |
| 16 Sep 2026 | 894 |
| 17 Sep 2026 | 894 |
| 18 Sep 2026 | 895 |
| 21 Sep 2026 | 898 |
| 22 Sep 2026 | 899 |
| 23 Sep 2026 | 905 |
| 24 Sep 2026 | 896 |
| 25 Sep 2026 | 923 |
| 28 Sep 2026 | 923 |
| 29 Sep 2026 | 925 |
| 30 Sep 2026 | 910 |
| 1 Oct 2026 | 915 |
| 2 Oct 2026 | 921 |
| 5 Oct 2026 | 924 |
| 6 Oct 2026 | 936 |
| 7 Oct 2026 | 942 |
| 8 Oct 2026 | 948 |
| 9 Oct 2026 | 947 |
| 12 Oct 2026 | 959 |
| 13 Oct 2026 | 955 |
| 14 Oct 2026 | 982 |
The same day
Other quakes on 14 October 2026
| Instrument | Move | Size |
|---|---|---|
| UnitedHealth UNH | +4.73% | +4.4σ |
| Bank of America BAC | −4.76% | −4.0σ |
| Lockheed Martin LMT | +3.61% | +3.5σ |
| AbbVie ABBV | +3.32% | +3.3σ |
| Pfizer PFE | +2.96% | +3.3σ |
| Silver SILVER | −6.10% | −3.3σ |
| TRON TRX | +1.56% | +3.3σ |
| Marvell Technology MRVL | −8.73% | −3.1σ |
Costco's other quakes
On record, newest first
- 25 September 2026: +2.93%, +3.1σ
- 9 July 2026: −4.21%, −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 Costco'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 Costco'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.