A steep selloff in South Korean stocks has continued, cutting the combined market capitalisation of the KOSPI and KOSDAQ by nearly 19 percent so far this month. Samsung Electronics and SK Hynix alone accounted for more than 940 trillion won of the decline, putting the 6,000 trillion won line at risk.

The Korea Exchange said the KOSPI market capitalisation totalled about 5,616.75 trillion won at Monday’s close, while the KOSDAQ stood at 440.384 trillion won. The combined market value of the two markets was 6,057.134 trillion won.

The combined market capitalisation of the KOSPI and KOSDAQ was 7,443.485 trillion won on June 30. That means it has fallen by 1,386.351 trillion won, or 18.6 percent, so far this month. The combined value rose to the 7,993 trillion won range on June 22, nearing a break above 8,000 trillion won.

It has dropped sharply this month as worries over a peak in the semiconductor cycle combined with renewed geopolitical tensions between the United States and Iran, and rising international oil prices. It fell to the 6,021 trillion won range the previous day, and dipped below 6,000 trillion won at one point during intraday trade on Monday.

The decline in market capitalisation was concentrated in Samsung Electronics and SK Hynix. Their combined market value has fallen by more than 940 trillion won this month.

Samsung Electronics ended Monday up 3.34 percent at 263,000 won. Its market value was about 1,538 trillion won, down 21 percent from 1,953 trillion won at the end of last month.

Samsung Electronics’ market value first topped 2,000 trillion won on June 1 and rose to the 2,119 trillion won range on June 18. It has remained below 2,000 trillion won this month as worries about a peak in the semiconductor cycle have grown.

SK Hynix closed Monday up 3.69 percent at 1,913,000 won. Its market value was about 1,363 trillion won, down 28 percent from 1,889 trillion won at the end of last month.

SK Hynix also exceeded 2,000 trillion won in market value at a closing price basis last month, but has continued to decline since then. Its market value fell sharply as the domestic share price slid after the listing of its American depositary receipts (ADRs).

Other top market-cap stocks also fell. SK Square dropped 30 percent to 157 trillion won from about 224 trillion won last month, and Samsung Electro-Mechanics fell 42 percent to 94 trillion won from 163 trillion won.

Hyundai Motor’s market value fell 14 percent to 87 trillion won from 101 trillion won, while LG Energy Solution slid by more than 11 percent to 75 trillion won from 85 trillion won.

The KOSPI market capitalisation has fallen by 1,312.79 trillion won this month, down 19 percent, while the KOSDAQ has shed about 73.56 trillion won, down 14 percent.