U.S. stock markets experienced significant gains on December 16, 2024, with the S&P 500 opening up 0.3% and the NASDAQ rising by 1.0% to reach an intraday record high of over 22,000. Throughout the day, the NASDAQ showed strong performance, initially up 0.5%, then hitting a 0.8% increase before closing with a 1.0% gain. This marks a notable achievement as the index continues to reach new highs, reflecting positive investor sentiment in the stock market.