Stock benchmarks closed sharply lower Monday, and the Dow marked its worst drop since late October, amid growing concerns about the global spread of the delta variant of the coronavirus that causes COVID-19. The Dow Jones Industrial Average /zigman2/quotes/210598065/realtime DJIA +0.08% shed about 726 points, or 2.1%, lower at 33,962 to mark its steepest slide since Oct. 28, 2020; the S&P 500 index /zigman2/quotes/210599714/realtime SPX +0.25% ended down 1.6% at 4,258, while the Nasdaq Composite Index /zigman2/quotes/210598365/realtime COMP +0.95% declined 1.1% at 14,275. All closing levels are on a preliminary basis. The declines for stocks came as the 10-year Treasury note yield /zigman2/quotes/211347051/realtime BX:TMUBMUSD10Y 0.00% fell to a five-month low beneath 1.18%. Stocks finished off their worst levels of the session, however, with the Dow down over 900 points at session lows.