Tokyo opened the week with a relief rally: the Nikkei added 0.5% and TOPIX outperformed as oil fell on a US-Iran pause, while the yen held near 163.5 and the TSE short-sell ratio printed 37.8% ahead of Friday’s BOJ decision.
The Nikkei 225 tells you what Japan’s most expensive stocks did; TOPIX tells you what the market did. A practical guide to price weighting, the NT ratio, and reading divergences between Japan’s two benchmark indices.
Tokyo’s chip complex bore the brunt of a global AI-spending scare on Friday: the Nikkei 225 fell 2.73% to 64,611 while defensives rallied, the yen held near 163.73, and the TSE short-selling ratio climbed to 43.8% — the top of its recent range.
Tokyo closed higher Thursday on renewed AI infrastructure optimism, with Advantest and SoftBank Group leading. Beneath the surface, the TSE short-sell ratio jumped to 43.2% of turnover and the Nikkei VI sits at a stressed 93rd percentile — a defensive tape wearing a bullish headline.
Tokyo surrendered an early tech-led rally on Tuesday, with the Nikkei 225 slipping 0.18% to 66,115.60 while banks and trading houses pushed TOPIX higher. The yen sank to 163.05 per dollar, JGB yields ground higher, and the TSE short-selling ratio jumped to 43.0% — the top of its recent range.
Why a weaker yen historically lifts Toyota, Sony, and the Nikkei — and when it stops working. A practical guide to the translation channel, assumed exchange rates, and reading USD/JPY alongside the Tokyo close.
Tokyo returned from the long weekend buying what it had sold: the Nikkei 225 jumped 3.26% to 66,232.19 with Advantest and SoftBank Group leading, all 17 sectors advanced, and the TSE short-selling ratio fell to 31.9% — the least defensive reading in over a week.
The Nikkei 225 is a price-weighted average, so a handful of high-priced chip names can move the whole index far more than their economic size suggests. This guide explains the mechanics, contrasts the Nikkei with TOPIX, walks through a real worked example, and shows how Japan’s semiconductor policy reinforces the sector’s outsized market role.
The Nikkei 225 fell 4.03% to 64,141.12 on Friday as a global tech rout hit Japanese chip names, with SoftBank Group down 9% and Tokyo Electron down 8.2%. The TSE short-selling ratio, notably, sat at the low end of its recent range — pointing to long liquidation rather than fresh shorting.
The Nikkei 225 fell 2.79% to 66,835.54 on Thursday as semiconductor and AI names were sold hard on valuation concerns. Autos rallied on a steady 162 yen, the short-sell ratio held at 37.4%, and the Nikkei VI sat at an elevated 32.27.