Wall Street faces danger signs after best quarter since '98

(Reuters) - A stock rebound marked by Wall Street's strongest quarter in more than two decades has slowed in recent weeks, as a resurgence in coronavirus cases threatens to derail the economy's recovery from a deep downturn. With the S&P 500 up 20% in the quarter ended on Tuesday and just 8% below its February record high, investors are parsing an array of factors that could weigh on stocks in the months ahead, including potential delays in reopening parts of the U.S. economy and sky-high stock..