The KOSPI index approximately doubled in the first half of 2026, recording a gain of around 100% over the January–June period, according to Finnhub. The advance was driven by surging demand for AI chips and strong performance from South Korean semiconductor companies Samsung Electronics and SK Hynix. The TAIEX rose 59% over the same period, and the Nikkei 225 gained 39%, reflecting broad-based strength across Asian technology markets.
Samsung Electronics (005930) and SK Hynix (000660), both listed on the KOSPI, were the principal drivers of the index's gain, with their performance directly tied to AI-related semiconductor demand. The TAIEX's 59% rise similarly reflects the weight of semiconductor and electronics manufacturers in Taiwan's benchmark index.
Market sentiment across the period was not uniform. Finnhub reported that January was characterised by optimism around US Federal Reserve rate cuts and strength in precious metals, while conditions became more cautious by June amid volatility in AI-related trades. This shift in sentiment accompanied the KOSPI's move even as the headline half-year return remained historically large.
Sources: Finnhub, Bloomberg Markets