NEW YORK—The year 2020 was a wild one for Wall Street, bookended by the end of the longest bull market in history with the battering of equities by the COVID-19 shutdowns, and a bungee-cord rebound on hopes for economic recovery that resulted in the shortest bear market on record. After closing at a record high on Feb. 19, stocks suffered a month-long plummet as the coronavirus pandemic and related government lockdowns sowed panic about the damage to the economy in the United States and globally. A 9.5 percent plummet in the S&P 500 on March 12, the benchmark index’s biggest-one day percentage drop since the “Black Monday” crash of 1987, put it down 26.7 percent from the February high and confirmed a bear market, widely viewed as a decline of more than 20 percent from a high. But the slide only lasted until March 23, when the S&P bottomed. It …