Live: S&P 500 closes higher to start October as Treasury yields retreat from multiyear highs [https://www.cnbc.com/2026/09/30/stock-market-today-live-updates.html?__source=iosappshare%7Ccom.apple.UIKit.activity.CopyToPasteboard](https://www.cnbc.com/2026/09/30/stock-market-today-live-updates.html?__source=iosappshare%7Ccom.apple.UIKit.activity.CopyToPasteboard)