Wall Street resumed its fourth-quarter rally today, pushing the Dow Jones industrials to its first close above 12,400 after a series of strong company earnings and a drop in unemployment claims revived investors’ confidence in the economy.

Wall Street rallied on a burst of optimism today as the multibillion-dollar buyout of HCA and upbeat earnings from drug manufacturers eased anxiety about an economic slowdown. The Dow Jones industrial average soared more than 180 points.