According to Jinshi Data, the major U.S. stock indexes fell before the Federal Reserve launched its first highly anticipated interest rate cut in more than four years, with market tensions over the extent of the rate cut dominating. Eight of the 11 sectors of the S&P 500 fell, while the medical sector rose slightly by 0.1%.

The Russell 2000 index, which tracks small-cap stocks, also fell 0.2%. Mixed economic indicators over the past month have made investors nervous ahead of the most unpredictable decision by the Federal Reserve in years.

CME Watch tool shows that recent dovish comments from current and former Fed officials have traders believing that there is a 53% chance of a further 50 basis point rate cut. Erica Groshen, senior economic adviser at Cornell University, said that if the Fed cuts by 50 basis points instead of 25 basis points, it will skip the rate cut next month. If the Fed cuts by 25 basis points, the Fed will raise interest rates faster next month.