BOJ Warns of Japan Stock Market Overheating, U.S. Trade Policy Risk

The Bank of Japan (BOJ) has warned that the Japanese stock market is showing early signs of "overheating," noting that uncertainty surrounding U.S. trade policies could trigger a significant market correction, which would, in turn, impact financial institutions. The Nikkei 225 (N225) hit a record high on Tuesday, buoyed by potential support for fiscal stimulus from Sanae Takaichi, who was vying to become Japan's first female prime minister. The index is up nearly 24% so far this year. The BOJ, in its semi-annual Financial System Report, noted that increased leverage and participation by foreign hedge funds in Japanese Government Bond (JGB) trading could amplify market volatility. The report stated, "If there are unexpected shifts in market conditions, rapid position adjustments by hedge funds, coupled with deleveraging, could magnify asset price volatility. Should such adjustments occur in the JGB market, it could impact a broad range of Japanese financial instruments." In April and May, rumors of a large increase in fiscal spending, potentially leading to larger debt issuance, triggered hedge funds to sell JGBs, causing yields on super-long bonds to spike. While yields have since stabilized, some analysts warn that Takaichi's proposed massive spending plans could trigger a fresh wave of JGB selling and yen depreciation. The Financial System Report included a "heat map" visualizing imbalances in asset prices and credit conditions, with "red" indicating overheating. The map showed that stock prices were in a "red" zone, while the remaining 13 categories were "green," indicating no significant deviations from trends. The report emphasized: "Given the market risk related to stocks held by the BOJ, it is necessary to closely monitor the price movements of risky assets, including the stock market." The report also mentioned that Japanese property prices, particularly in major metropolitan areas, are rising, driven by investment demand from foreign investors and others. The report stated, "If market participants' expectations regarding future real estate demand change, it could trigger a housing price correction... Given the continued increase in banks' real estate-related exposure, real estate market dynamics still need to be closely monitored." However, the BOJ also noted in the report that the Japanese financial system remains generally stable, with banks possessing strong capital bases, stable funding sources, and an ability to withstand various shocks. The BOJ continually monitors for signals of financial imbalances that could trigger a financial crisis, such as asset price bubbles and excessive credit expansion. While economic and price trends are the primary determinants of monetary policy, the central bank also considers conclusions related to financial imbalances when making decisions. Critics argue that the BOJ's long-held ultra-low interest rates and a weak yen have reduced the cost for foreign investors to invest in the Japanese market, a key driver behind rising asset and property prices. Data from the Real Estate Economic Institute of Japan shows that the average price of new apartments in the Tokyo metropolitan area rose 20.4% year-on-year between April and September. The BOJ abandoned its decade-long aggressive stimulus program last year and raised the short-term interest rate to 0.5% in January, believing that Japan was nearing its 2% inflation target. However, BOJ Governor Kazuo Ueda has emphasized that further interest rate hikes need to proceed cautiously due to uncertainty regarding the impact of U.S. tariffs on the Japanese economy. A Reuters poll earlier this month indicated that most economists expect the BOJ to raise interest rates again in the fourth quarter, possibly as early as next week.

Analyzing Potential Impacts of Market Fluctuations