S&P 500 and Nasdaq close at lowest levels in over a month as oil and yields bite

The S&P 500 slid to roughly 7,586.84 on Monday, a drop of about 0.43% that left the index at its lowest closing level in six weeks. The Nasdaq followed it down, extending a brutal stretch for equities that has now erased most of the summer’s gains. Oil above $100 and yields near 5% Brent crude surged past $109 per barrel, gaining roughly 3% in a single session. West Texas Intermediate pushed above $105, fueled by supply anxieties tied to geopolitical friction in the Middle East involving Iran and Saudi production disruptions. On the bond side, the 10-year Treasury yield climbed toward the 4.99% to 5.04% range. That neighborhood hasn’t been visited since 2007. When risk-free government debt is paying nearly 5%, the argument for holding volatile stocks gets a lot harder to make. Higher yields raise the discount rate applied to future corporate earnings. That math hits growth and tech stocks hardest, since so much of their valuation rests on profits expected years from now. Four straight days of losses set the stage Monday’s decline wasn’t a one-off. The S&P 500 had already posted four consecutive losing sessions through September 10, shedding between 0.5% and 0.7% per day dur...