日本版“特拉斯冲击”或将上演，超长债供需失衡尚未完全定价

Core Insights - Japan is facing significant fiscal risks similar to the "Truss Shock" in the UK, as the market has not fully priced in the deterioration of supply and demand for ultra-long-term government bonds [1][4] - The Japanese government is finalizing a large-scale economic stimulus plan, with government spending estimated at 21.3 trillion yen, potentially reaching a total of 42.8 trillion yen when including private sector investments, raising concerns about fiscal discipline [1][6] - The Japanese bond market is experiencing a severe sell-off, with the 30-year government bond yield hitting a historical high, and both 10-year and 5-year yields reaching their highest levels since 2008 [1][4] Fiscal Policy Concerns - Nomura Securities warns that ongoing concerns about a "Truss Shock" will lead foreign investors to continue avoiding the Japanese market, exacerbated by a weakening yen and poor performance of ultra-long-term bonds [4][6] - The market is focused on whether the ruling Liberal Democratic Party can gain momentum for further fiscal expansion, which could heighten concerns about fiscal policy [6][7] - The Japanese Finance Minister has raised the urgency of addressing yen depreciation, indicating that the quality and scale of economic stimulus measures should not undermine confidence in the yen or Japanese government bonds [7][8] Yield Curve Dynamics - There is significant potential for the steepening of the yield curve if the supply and demand for ultra-long-term bonds deteriorate further, with the current supply premium indicator for 30-year bonds at 48 basis points, down from a peak of 67 basis points earlier this year [6][8] - The analysis indicates that the yield curve steepening driven by fiscal concerns has not fully reflected the extent of supply and demand deterioration observed in April and May [8][10] Market Reactions - The market's response suggests a lack of effective communication from the government, as expectations for interest rate hikes have not changed despite discussions between the Prime Minister and the Bank of Japan Governor [7][8] - The current market conditions reflect deep investor concerns regarding Japan's policy outlook, emphasizing the need for the government to balance economic stimulus with maintaining fiscal credibility to avoid a "Truss Shock" scenario [10]