#TradFi交易分享挑战 The Nikkei Index Reaches New Highs Again: The Driving Force of the AI Wave and the Defense of Exchange Rate Thresholds

#TradFi交易分享挑战 The Nikkei Index Reaches New Highs Again: The Driving Force of the AI Wave and the Defense of Exchange Rate Thresholds

1. Semiconductor and AI Concept Stocks Ignite the Nikkei Index, Leading Stocks Perform Brightly Since May 2026, the Japanese stock market has staged a historic rally. On May 7, the Nikkei 225 Index surged by 3,320.72 points, setting a single-day record for the largest increase, breaking through the 63,000-point mark for the first time, with the year-to-date increase exceeding 20%. The core driver of this surge comes from the concentrated breakout of global semiconductor and AI concept stocks. Amid the global wave of AI infrastructure development, high-bandwidth memory (HBM) faces structural shortages, and storage chips are entering a price increase cycle. SK Hynix and Samsung Electronics have both confirmed that their HBM capacity for 2026 is 100% sold out, with customers even pre-ordering capacity for 2027 in bulk. Leading storage chip companies like Intel and Micron Technology in the US continue to see large gains. The expansion race among storage giants in the US, Japan, and South Korea directly boosts order expectations for upstream Japanese semiconductor equipment and materials manufacturers, with related leading stocks performing especially well.

On May 7, the SoftBank Group's stock price soared over 18%; the packaging substrate giant Ibiden rose over 22%, continuing to hit a new high on May 12; at the same time, high-tech leaders such as Tokyo Electron, Advantest, Renesas Electronics, Rorze Semiconductor, Lasertec (EUV mask inspection equipment), Shin-Etsu Chemical, SUMCO, JSR, and Tokyo Ohka Kogyo all showed strong upward momentum. However, like most global stock markets, the Japanese market also exhibits overall structural differentiation. The recent rise in the Nikkei was mainly driven by a few heavyweight stocks such as SoftBank, Tokyo Electron, and Advantest, and tech stocks in the chip sector, while most other stocks did not follow suit, resulting in the broader TOPIX index underperforming. The Nikkei's performance is somewhat disconnected from Japan's weak economic fundamentals. On April 28, the Bank of Japan lowered its GDP growth forecast for fiscal year 2026 from 1.0% to 0.5%, while raising the core CPI forecast from 1.9% to 2.8%. Internal disagreements over the path of interest rate hikes have emerged, and the market is already expecting the Bank of Japan to possibly raise interest rates again in June or July.

2. The Yen Breaks Below 160, Japan Launches a "Currency Defense War"
Since April last year, the Nikkei index has continued to rise, but the yen has come under significant pressure. Looking back at the data, the USD/JPY exchange rate has fallen from around the 130 level; by April 2024, depreciation pressures have intensified further. On April 29, the USD/JPY exchange rate broke below the important psychological threshold of 160, hitting a low not seen since 1990. In response to this sharp volatility, the market widely speculates that the Bank of Japan took intensive "suspected intervention actions" around April 30 to curb excessive speculative depreciation of the yen.
Most believe that the immediate trigger for this suspected intervention was the USD/JPY exchange rate falling below the critical psychological level of 160, which had previously been a sensitive zone indicating potential intervention willingness by Japanese authorities in 2024. Looking deeper, the persistent weakness of the yen is mainly influenced by three intertwined factors: the high US-Japan interest rate differential, the Bank of Japan's monetary policy normalization lagging behind market expectations, and ongoing investor concerns over potential risks of Japan’s expansionary fiscal policies. It is estimated that the Japanese government and the Bank of Japan used about $34.5 billion (roughly 5 trillion yen) in foreign exchange reserves for intervention around April 30. Supported by this, the USD/JPY rate rebounded significantly from the 160 low. Subsequently, during May 1, 4, and 6 (during Japan’s Golden Week), market volatility again showed typical intervention characteristics, with the USD/JPY rate oscillating within the 155-157 range. Based on comprehensive analysis of abnormal market fluctuations and capital flow data, the total potential intervention scale is estimated to be close to $70 billion (about 10 trillion yen).
Most believe that the Japanese authorities used a combination of "verbal guidance, precise timing, and moderate-scale intervention" strategies, with an estimated cost of about 5 trillion yen, to effectively deter speculative short positions in the short term. This operation not only temporarily stabilized the critical psychological threshold of 160 but also significantly reduced the risk of the market falling into an uncontrolled depreciation spiral. However, whether the yen can truly stabilize in the medium to long term still depends on the Bank of Japan’s resolve to normalize monetary policy, the Federal Reserve’s interest rate policies, and progress in Japan’s domestic fiscal reforms.
Foreign exchange intervention is merely a "painkiller," not a "cure." Over the past decade, global investors have borrowed nearly zero-cost yen to invest in high-yield US bonds, emerging market debt, and tech stocks. Once the Bank of Japan raises interest rates substantially and signals continued tightening, narrowing interest rate spreads will force large-scale margin calls. The "Black Monday" in August 2024 prefigured this scenario: the yen surged sharply, triggering algorithmic trading stop-losses, the VIX spiked in a single day, and the Nikkei plunged, triggering a global stock market decline. If rate hikes become a trend rather than a one-off event, the unwinding will shift from "event-driven" to "trend-driven," and systemic reassessment of volatility premiums in the global forex market will occur.

3. CME Micro Nikkei 225 Index Futures: A More Flexible Tool for Japanese Stock Participation
Against the backdrop of high global capital attention to Japanese stock volatility, offshore derivatives markets are becoming an important window into risk management trends. For example, the CME launched micro Nikkei 225 index futures in Q4 2024, offering a lower participation threshold and more flexible hedging options.
As a price-weighted index, the Nikkei 225 reflects the performance of 225 blue-chip companies listed on the Tokyo Stock Exchange. Since its launch, over 1.6 million contracts have been traded. Notably, the trading activity of these contracts highlights the function of cross-timezone pricing. Data shows that about 67% of related trades in 2025 occurred during the after-hours trading sessions in the US and Europe, after the Tokyo market closed. This means that even when Japan’s domestic market is closed, global investors can still adjust their positions in a timely manner based on Bank of Japan (BoJ) interest rate decisions or suspected currency interventions. The distribution of this trading structure reflects the increasing reliance of international capital on non-local risk management tools to respond to Japan’s policy volatility. $JPN225