日本股市，突发！

Core Viewpoint - The Japanese stock market experienced fluctuations following positive news, including the reduction of U.S. tariffs on Japanese cars and expectations that the Bank of Japan may halt interest rate hikes [1][5][6]. Group 1: Market Reactions - The Nikkei 225 index initially surged past the 45,000 mark, reaching a historical high before reversing direction and declining [1][3]. - As of the latest report, the Nikkei 225 index was down 0.20%, standing at 44,678.39 points [3]. Group 2: U.S. Tariff Changes - The U.S. government announced a reduction in import tariffs on Japanese cars from 25% to 15%, effective from September 16 [5]. - This tariff adjustment aligns with the U.S.-Japan trade agreement, which imposes a 15% tariff on most Japanese imports, including automobiles and parts [5]. Group 3: Bank of Japan's Monetary Policy - The Bank of Japan is expected to maintain its current interest rate of 0.5% during the upcoming meeting, with analysts suggesting that any rate hike may not occur until January 2026 [6][7]. - Economic indicators show a decline in exports and industrial output, particularly in the automotive sector, which may influence the Bank's decision to keep rates unchanged [7]. Group 4: Political Factors - The market is optimistic about the upcoming leadership election in Japan, with former Economic Security Minister Sanae Takaichi being a leading candidate who supports increased fiscal stimulus and monetary easing [8]. - The ruling party plans to announce the presidential election on September 22, with voting scheduled for October 4 [8].