跌超19%，拖累道指，黄金、原油齐涨

Market Overview - The U.S. stock market showed mixed results, with technology and semiconductor stocks rising, while the Dow Jones Industrial Average was dragged down by a significant drop in UnitedHealth Group, which fell over 19% [3] - The S&P 500 index increased by 0.41% to 6978.60 points, and the Nasdaq Composite rose by 0.91% to 23817.10 points, while the Dow Jones index decreased by 0.83% to 49003.41 points [3] Currency and Trade Policy - The U.S. dollar index has been declining, with President Trump signaling that he is not concerned about the dollar's depreciation [4] - The U.S. continues to adjust its trade policies, maintaining a 50% tariff rate on Indian goods and threatening to raise tariffs on certain South Korean products to 25% [4] Semiconductor Sector - The Philadelphia Semiconductor Index reached a new high, increasing by 2.40% [8] - Micron Technology announced a $24 billion investment plan to build a new memory chip manufacturing facility in Singapore, aimed at increasing production amid a global shortage [9] - This investment is expected to create synergies between NAND flash memory and DRAM production, driven by the rising demand from AI and data-centric applications [9] Technology Giants - Among the "Big Seven" tech companies, only Tesla saw a decline of 0.99%, while Amazon and Microsoft rose over 2% [12] - Google announced a price adjustment for data transmission methods in North America, set to double by May 1, 2026 [12] - Microsoft introduced the MAIA 200 chip, an AI inference accelerator based on TSMC's 3nm process, which will support various AI models, including OpenAI's latest GPT-5.2 [12] Commodity Prices - Gold prices continued to rise, reaching $5160 per ounce, driven by geopolitical tensions and central banks accumulating gold as a fundamental currency [14] - International oil prices also increased, with NYMEX WTI crude oil futures closing above $60 per barrel [14]