Korea — Too Far Up, Now Too Far Down

Seoul fell for the sixth session in a row on Tuesday. The Kospi lost 3.7% to 5,552.74 — a 13.0% drop in six days — with SK Hynix down 4.2% at 1.223 million won and Samsung Electronics down 3.0% at 211,500 won, as doubts about AI spending returned to the market most exposed to it, as reported by Investing.com. The fall looks dramatic on its own. It looks different next to the run that came before it — because no market in the AI trade ran further, faster, than Korea.

The run, measured

A year ago the Kospi stood at 3,815. By 22 June it had reached 9,115 — up 139% in eight months, carried by the two companies that make the memory chips AI training runs on. SK Hynix went up sixfold in the same stretch; Samsung almost quadrupled.

Table as text

Daily closes	20 Oct 2025	June peak	Today	From peak	Still up 12m
Kospi	3,815	9,115 (22 Jun)	5,553	−39.1%	+45.6%
Samsung Electronics	98,100	362,500 (18 Jun)	211,500	−41.7%	+115.6%
SK Hynix	485,500	2,919,000 (22 Jun)	1,223,000	−58.1%	+151.9%

Daily closing prices from EODHD and Yahoo Finance; Korean prices in won.

Note the date in that middle column. The Kospi and SK Hynix peaked on 22 June — the same day the Philadelphia chip index set the record it now sits 22.7% below. The memory trade topped globally on one calendar day, and it has been unwinding on both sides of the Pacific ever since. Korea just carries the bigger amplitude, in both directions.