News Number of the Day S&P 500 Ends Lousy Week on Optimistic Note Number of the Day: The most relevant or interesting figure in personal finance By Diccon Hyatt Published on October 1, 2021 Photo: The Balance That’s how many weeks it’s been since the S&P 500 had as bad a week as this last one, although promising results from a Merck COVID-19 pill boosted stocks to a Friday rebound. The benchmark stock index closed at 4,357, falling 1.92% for the week, the biggest decline since February. Further signs that inflation may persist longer than expected, combined with other bad economic data, alarmed investors. The index lost 4.8% in September, the biggest monthly loss since the pandemic hit in early 2020. But the market rallied to a better start in October, with the S&P 500 posting a 1.15% gain after drugmaker Merck announced positive trial results from a COVID-19 pill. Have a question, comment, or story to share? You can reach Diccon at dhyatt@thebalance.com. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources The Balance uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Federal Reserve Economic Data. “S&P 500, Weekly Percent Change.” Federal Reserve Economic Data. “S&P 500, Monthly Percent Change.” Merck. “Merck and Ridgeback’s Investigational Oral Antiviral Molnupiravir Reduced the Risk of Hospitalization or Death by Approximately 50 Percent Compared to Placebo for Patients with Mild or Moderate COVID-19 in Positive Interim Analysis of Phase 3 Study.” Emory. “EUA application expected for COVID-19 antiviral discovered at Emory.”