South Korean stock markets closed the week on a high note, extending a robust five-day winning streak driven by cooling U.S. inflation data and strong foreign buying.

On August 14, the benchmark KOSPI jumped 164.60 points (2.42%) to finish the session at 6,977.94. The index opened sharply higher at 6,995.67—up 182.33 points or 2.68%—and briefly pierced the psychological 7,000 threshold, touching an intraday high of 7,010.86 (2.90%).

For the entire week, the KOSPI surged an impressive 11.5%, marking its highest weekly return since late May, when the market recorded a 13.63% weekly gain following its historic first breakout above the 7,000 mark.

Meanwhile, the tech-heavy KOSDAQ also maintained upward momentum. After opening at 868.07 (up 6.70 points or 0.78%), it closed up 3.28 points (0.38%) at 864.65. The KOSDAQ recorded a weekly gain of 8.2% and has skyrocketed 20.1% since the beginning of the month.

Key Stock Movements: Semiconductor Giants Lead

Major blue-chip stocks spearheaded Friday's market advance:

Samsung Electronics gained 2.43% on the day, capping off a stellar weekly surge of 18.8% and a 4.6% increase compared to the end of last month.
SK Hynix rose 3.26%, bringing its weekly gain to 15.7%. However, its monthly return showed a slight contraction of 4.2%, largely due to a record-breaking upper-limit surge (29.95%) on the comparison baseline date of July 31.

Investor Sentiment and Trading Activity

Foreign investors emerged as the primary driving force behind the market rally, heavily net-buying 3.0486 trillion won to extend their buying streak to four consecutive sessions.

In contrast, institutional investors shifted their stance to net-sellers, offloading 1.03 trillion won after five straight sessions of net-buying. Retail investors continued their outflow, recording a net sale of 1.9818 trillion won for the day, marking four consecutive days of profit-taking.

On the KOSDAQ market, retail investors stepped in as the main buyers with 315.1 billion won in net purchases, while foreigners and institutions recorded net sales of 67.3 billion won and 253.0 billion won, respectively.

Macroeconomic Factors: Inflation Strains Ease

Global macroeconomic indicators provided significant tailwinds for risk-on sentiment. Following a softer-than-expected U.S. Consumer Price Index (CPI), the Producer Price Index (PPI) for July also demonstrated clear signs of cooling inflation.

U.S. July PPI remained flat month-on-month (0.0%), coming in well below market expectations of a 0.2% rise.
Year-on-year PPI growth slowed to 4.7%, down notably from 5.5% the previous month.
These cooling figures significantly diminished expectations of aggressive U.S. Federal Reserve interest rate hikes, fueling sustained appetite for global risk assets.

Additionally, easing energy pressures contributed to market stability. October-delivery Brent crude and September-delivery West Texas Intermediate (WTI) fell 2.15% and 2.43%, settling at $87.07 and $81.25 per barrel, respectively.

In the Seoul foreign exchange market, the won-to-dollar exchange rate finished down 1.1 won at 1,418.3 won as of 3:30 PM.