The Korean stock market saw 29 cases of closing price volatility investment caution designations in May-July, a 7.25-fold increase from 4 cases in the same period last year, according to Korea Exchange (KRX) listing disclosure system (KIND) data. The designations occur when closing prices suddenly jump or fall during the simultaneous call auction period that ends daily trading on the KOSPI market, triggered by concentrated buy or sell orders. The surge in volatility cases coincides with broader market instability, as the VKOSPI volatility index averaged 80.22 in May-July compared to 22.15 in the same period last year.
Monthly Cases Rose from 6 to 13 Across May-July
Closing price volatility designations increased for three consecutive months: 6 cases in May, 10 in June, and 13 in July. This contrasts with only 6 cases total in the preceding three months of February-April. The May-July figure also represents a fourfold increase compared to 7 cases in the same period in 2024.
A closing price volatility designation is triggered when the closing price moves 5% or more from the previous execution price, closing volume represents 5% or more of total daily volume, and daily trading volume exceeds 30,000 shares. The system alerts investors to stocks where concentrated buy or sell orders during the closing auction cause the final execution price to differ significantly from the previous price.
Major Stocks Including Doosan and Samsung Card Designated
The 29 designations included companies of varying market capitalizations. In May, Kakao Pay, SK IE Technology, and Husung received designations. June designations included KT, Doosan, Hyundai E&C, KEPCO KPS, KEPCO Engineering & Construction, and POSCO DX. July designations included Samsung Card, Korean Air, Cheil Industries, S1, and SL.
VKOSPI Volatility Index Tripled Year-Over-Year
The VKOSPI volatility index, calculated based on daily closing prices of KOSPI200, averaged 80.22 in May-July compared to 22.15 in the same period last year, a 3.6-fold increase. A Capital Market Institute analysis released on the 27th of last month showed that volatility expansion in the domestic stock market reached unusual levels. According to the report, daily return volatility of the KOSPI in the first half reached 3.6%, more than double last year's 1.4%. In March and June, volatility reached 4.8% and 4.7% respectively, exceeding the 4.2% recorded in March 2020 during the COVID-19 shock.
Researchers Recommend Enhanced Volatility Mitigation Measures
While closing price volatility designations do not confirm unfair trading, the sharp increase in cases where closing prices used for fund and ETF benchmark pricing, derivatives valuation, and institutional investor performance measurement were significantly affected by last-minute orders indicates a need to review the closing price formation process.
Capital Market Institute researchers Kim Jun-seok and Jang Geun-hyuk stated, "Focus should be on mitigating short-term volatility from concentration and distortion without hindering price adjustments based on information." They explained that price impact from orders concentrated on specific stocks and time periods should be reduced through expanded use of weight-limited indices, enhanced effectiveness of volatility mitigation mechanisms, and activation of inter-institutional large-scale trading platforms.
FAQ
What caused the 7.25-fold increase in Korean stock closing price volatility cases in May-July?
The Korea Exchange recorded 29 closing price volatility investment caution designations in May-July, compared to 4 cases in the same period last year. The designations resulted from concentrated buy or sell orders during the simultaneous call auction period that ends daily KOSPI trading, causing closing prices to move significantly from previous execution prices.
Which major Korean stocks received closing price volatility designations?
Designated stocks included Doosan, Samsung Card, Hyundai E&C, KT, Kakao Pay, SK IE Technology, Korean Air, Cheil Industries, S1, KEPCO KPS, KEPCO Engineering & Construction, POSCO DX, and SL across May-July.
How did the VKOSPI volatility index change in May-July compared to last year?
The VKOSPI volatility index averaged 80.22 in May-July, a 3.6-fold increase from 22.15 in the same period last year. Daily return volatility of the KOSPI in the first half reached 3.6%, more than double last year's 1.4%.
