Group 1 - The Dow Jones Industrial Average (DJIA) reached an intraday all-time high of 45,203.52 points before closing nearly flat at 44,946.12 points, up only 34.86 points, indicating a less than 0.1% increase [2] - UnitedHealth (UNH.US) saw its stock price surge nearly 12%, marking its largest single-day gain since November 2020, largely due to Berkshire Hathaway's disclosed holdings in the latest quarterly filing [2] - Despite a year-to-date decline of over 40%, UnitedHealth's stock price fluctuations significantly impacted the DJIA, contributing over 167 points to the index's performance [2] Group 2 - The S&P 500 and Nasdaq Composite indices experienced declines of 0.29% and 0.40%, respectively, indicating a divergence in performance among the three major U.S. stock indices for the first time in 2025 [2] - Analysts noted that the DJIA, being a price-weighted index, is more susceptible to individual stock price movements compared to the market capitalization-weighted S&P 500 [3] - The limited number of components in the DJIA and its price-weighted nature mean it does not fully reflect the overall market value, leading to a cautious approach in its investment significance [3]