The U.S. stock market has reached unprecedented levels in early 2025, with the Nasdaq's market capitalization to U.S. GDP ratio hitting a record 103%. This marks a rise of approximately 40 percentage points since its October 2022 low and surpasses the previous high recorded in 2021. Additionally, the U.S. now accounts for 67% of the MSCI All-Country World Index, an all-time high, reflecting a doubling of its share over the past 30 years. In terms of valuation, the S&P 500's CAPE ratio stands at 33x, the highest since the 2000 Dot-Com Bubble, while tech stocks have an even higher CAPE ratio of around 60x, indicating that U.S. equities are currently the most expensive globally. This situation raises concerns about market sustainability and potential implications for investors.