Stocks plunged on Friday, with the Dow Jones Industrial Average suffering its worst one-day loss since the throes of the pandemic, as the latest raft of corporate earnings and the prospect of rising rates spurred a wave of selling. The Dow fell 981.36 points, or 2.8%, to 33,811.40. The S&P 500 was 2.8% lower at 4,271.78, for its worst day since March.