KOSPI Volatility Peaks as Chip Weighting Drives Market Swings
South Korea's benchmark index faced record volatility as semiconductor concentration and leveraged funds amplified price swings.
The KOSPI index tested the 7,000 level on Thursday, dipping to 6,920 before closing at 7,058.06 with a 0.09% gain. The Bank of Korea identified the market's daily volatility at 4.1%, a figure that is double the levels observed in Japan and Taiwan. This heightened instability coincided with net foreign selling of 496.4 billion won, pressuring major issuers including Samsung Electronics, SK Hynix, Hyundai Motor, and LG Energy Solution during the session.
The central bank’s September credit report attributes the recent sharp corrections to the index's structural reliance on the semiconductor sector. Samsung and SK Hynix account for 51.2% of the KOSPI's total weight. During the previous month's decline from 9,200 to the 6,200 range, these two companies drove 69.3% of the index's total loss, exposing the broader market to concentrated sector risks.
Leveraged Funds Amplify Sector Swings
Deputy Governor Park Jong-woo highlighted the rapid expansion of two-times leveraged ETFs tied to the major chipmakers. These funds grew from 3.33 billion dollars to 10.7 billion dollars in a single month following their May listing. The surge in leveraged exposure, combined with record retail margin loans that subsequently unwound, created a feedback loop that accelerated both the rally and the subsequent correction.
The Bank of Korea has recommended closer monitoring of these instruments, noting that the recent reduction in their size does not eliminate the need for continued oversight. The concentration of financial instruments in a narrow industrial segment remains a primary driver of the index's erratic behavior, distinct from broader macroeconomic factors.
External Pressures Impact Import Economy
Thursday's trading session was further complicated by external macroeconomic pressures. Brent crude oil remained above 100 dollars per barrel due to renewed geopolitical tensions, while the US 10-year Treasury yield hovered near 4.84%. South Korea's economy, which relies heavily on imported energy, faces direct cost implications from these levels, adding a layer of uncertainty to equity valuations.
The session also coincided with quadruple witching, a period where multiple derivatives contracts expire simultaneously, which typically increases trading volume and volatility. According to reports from GN stocks/banks, analysts such as Han Ji-young from Kiwoom Securities suggest that corporate buybacks and the return of foreign capital may provide necessary support to stabilize the index against these external shocks.
