Investor sentiment in the U.S. stock market has reached unprecedented levels, with 56% of Americans expecting stock prices to rise over the next 12 months, according to recent data from the Conference Board. This figure marks the highest level of optimism recorded since the survey began in 1987. Additionally, foreign holdings of U.S. stocks have surged to an all-time high allocation of approximately 60%, a 15 percentage point increase over the past four years, surpassing levels seen during the 2000 Dot-com bubble. In November, U.S. equity ETFs and mutual funds experienced the largest monthly inflow on record, contributing to the biggest three-month inflows since 2021. The S&P 500's market capitalization as a share of world GDP has reached a record 46%, exceeding the previous peak of 42% prior to the 2022 bear market. Furthermore, net long positioning in S&P 500 futures by institutional investors has reached around 240,000 contracts, the highest on record, indicating a significant bullish sentiment among asset managers and leveraged funds. Despite these indicators of market euphoria, there are concerns about potential overvaluation and the risks associated with high levels of investor speculation.