U.S. stock markets experienced volatility as the S&P 500 and NASDAQ reached new record highs earlier in the week, driven by a surge in technology shares. On December 4, S&P 500 futures rose to a new record high, and both the S&P 500 and NASDAQ closed at record levels, reflecting strong investor sentiment. However, on December 5, the markets dipped, with the Dow Jones Industrial Average falling by 248.33 points, or 0.55%, while the NASDAQ and S&P 500 dropped by 0.18% and 0.19%, respectively. This decline was attributed to a sharp decrease in shares of UnitedHealth and other tech stocks, as investors adopted a cautious stance ahead of a key jobs report scheduled for release on December 6. The market remains sensitive to valuation concerns despite earlier gains.