Correction — 22 October 2026: The original 4.00% KOSPI gain had the wrong sign. The daily comparison gives a 0.58% decline. Claims of a sharp Korean rally and associated regional capital rotation are withdrawn. This is a retrospective review using daily history retrieved on 2026-10-22, not a live report or a reconstruction of every quote available at original publication.
Reconstructing the Korean return
The Korean index moved from 6,995.39 on 2026-09-07 to 6,954.52 on 2026-09-08. Dividing the later value by the earlier value, subtracting one and multiplying by 100 gives -0.58%. The previous article reported +4.00%. The difference is material because it reverses the direction of the return.
Dated observations and calculations
| Series / source | Previous date | Previous value | Observation date | Value | Change | Time zone |
|---|---|---|---|---|---|---|
| KOSPI | 2026-09-07 | 6,995.39 | 2026-09-08 | 6,954.52 | -0.58% | Asia/Seoul |
| S&P 500 | 2026-09-04 | 7,718.60 | 2026-09-08 | 7,673.52 | -0.58% | America/New_York |
| Nasdaq Composite | 2026-09-04 | 26,506.99 | 2026-09-08 | 26,421.41 | -0.32% | America/New_York |
| US 10-year yield proxy (^TNX) | 2026-09-04 | 4.784 | 2026-09-08 | 4.806 | +2.2 bp | America/Chicago |
| WTI futures (CL=F) | 2026-09-04 | 91.48 | 2026-09-08 | 93.03 | +1.69% | America/New_York |
| Gold futures (GC=F) | 2026-09-04 | 4,476.60 | 2026-09-08 | 4,439.00 | -0.84% | America/New_York |
| USD/KRW (won per dollar) | 2026-09-07 | 1,345.06 | 2026-09-08 | 1,343.57 | -0.11% | Europe/London |
| USD/JPY (yen per dollar) | 2026-09-07 | 156.20 | 2026-09-08 | 153.85 | -1.50% | Europe/London |
| VIX | 2026-09-07 | 15.30 | 2026-09-08 | 15.72 | +2.75% | America/Chicago |
A direction error changes the regional comparison
KOSPI and the S&P 500 each declined about 0.58%, while the Nasdaq fell 0.32% in its US session. These numbers do not support the earlier story of Korea surging as Wall Street cooled. Similar percentage declines still do not prove a common cause: the markets close at different times and contain different companies. No yuan series was collected, so this article makes no yuan-performance claim.
Method and limits
Percentage changes use (value ÷ previous available daily value − 1) × 100, before rounding. Yield changes use the difference in percentage-point quotes multiplied by 100 to obtain basis points. Currency values are local-currency units per US dollar. Index levels are in points; futures quotes are in US dollars per barrel for WTI and per troy ounce for gold.
Each linked Yahoo Finance history is the data source for that row. These provider observations have not been independently checked against exchange settlement records. The futures series can change its referenced contract over time and should not be treated as the return on a continuously held investment. A date shared by two markets does not make their closing times simultaneous.
The earlier news-based explanations are omitted because their relevance to these measured moves was not established. For the calculation workflow and trading-session examples, see How to Read Daily Market Returns Without Mixing Trading Sessions.
