Domestic Listed Companies' Market Cap Plunges by W389 Trillion in a Single Day Amid Market Slump

As the domestic stock market plummeted today (October 15), the combined market capitalization of the Kospi and Kosdaq markets shrank by nearly 400 trillion won compared to the previous day during trading.

As of 10:13 a.m. today, the market capitalization of the Kospi stood at 4,600 trillion 963 billion won, down 356 trillion 1510 billion won (7.18%) from the previous day's closing price of 4,957 trillion 1140 billion won.

The market capitalization of the Kosdaq also decreased by 33 trillion 2520 billion won (7.16%) from the previous day.

This means that a total of 389 trillion 40 billion won in market capitalization evaporated across both markets in a single day.

In particular, simultaneous declines in the stock prices of Samsung Electronics and SK Hynix, the top two firms by market capitalization, amplified the overall drop in market value.

At the same time, Samsung Electronics' market cap decreased by about 114 trillion won to 1,242 trillion 3340 billion won, while SK Hynix also saw a drop of about 114 trillion won, coming in at 922 trillion 6110 billion won.

The decline in market cap from these two stocks accounted for 64% of the total decrease in the Kospi market.

Amid a semiconductor boom earlier this year, their market caps each surpassed 2,000 trillion won, but the situation is different now.

Looking at recent conditions, negative factors included news of capacity expansion and rapid progress by China's ChangXin Memory Technologies (CXMT), along with concerns over bottlenecks in AI infrastructure investment financing.

Furthermore, the continued weakness of tech and semiconductor stocks in the U.S. stock market overnight has compounded the downward trend for both stocks.

Concerns have resurfaced that big tech's reckless competition in AI infrastructure investment may fail to generate sufficient profitability relative to the scale of investment, which appears to have impacted semiconductor-related stocks.

Market research firm Gartner projected that about 1 trillion dollars will be invested this year, followed by an additional 6 trillion dollars in AI infrastructure investments from 2027 to 2030.

It estimated that achieving a 12% return on invested capital while covering investment and financial costs would require a cumulative 8.5 trillion dollars in revenue by 2030, whereas enterprise and consumer AI revenues stemming from AI data centers over the same period are projected to reach a maximum of only 3.6 trillion dollars.


In particular, SK Hynix's market capitalization fell below 1,000 trillion won.

The last time its market cap closed below 1,000 trillion won was on July 30.

Currently, Samsung Electronics is trading at 212,500 won, down 8.41% from the previous day.

During trading, it dropped to as low as 212,000 won, recording its lowest level since July 30 (when it hit 202,000 won during trading).

SK Hynix is also trading down 10.99% at 1,263,000 won.

Its intraday low reached 1,261,000 won, the lowest since July 29 (1,246,000 won).

The Kospi stood at 5,572.24, down 436.57 points (7.27%) from the previous day.

During trading, it slumped to 5,534.24 (-7.90%), dropping to the 5,500 range during trading for the first time since July 30.

In particular, foreign investors are dragging down the index by net selling 2 trillion 1365 billion won in the main bourse.

This marks an eighth consecutive trading day of selling streaks up to this day.

Institutions and retail investors are net buying 1 trillion 2375 billion won and 712.4 billion won, respectively.

The Kosdaq index stands at 763.58, down 60.30 points (7.32%).

(Photo: Yonhap News)
※ Please note: This article was translated by AI and may contain errors.