The market capitalization of the 10 largest US stocks now accounts for over 13% of the global stock market value, surpassing the Dot-com bubble peak of 9.9% seen in March 2000. Additionally, the 'Magnificent 7' stocks constitute approximately 32% of the S&P 500, a share that has increased by 10 percentage points in just 1.5 years. This concentration has led to the S&P 500 being one of the most expensive markets in history, with forward Price-to-Earnings (P/E) ratios at around 22x, the highest at the onset of a Federal Reserve cutting cycle in at least 60 years. The S&P 500 is expensive on 19 out of 20 metrics, with some metrics like the Shiller P/E (CAPE) being over 100% above historical averages. US technology stock prices are approximately 2x larger relative to the S&P 500, marking the largest outperformance in history. Ten companies make up 43% of the market cap of the 500 biggest companies.