U.S. stocks climbed on Thursday, extending gains into a fourth session, after the European Central Bank unfurled expanded stimulus and companies including Southwest Airlines (LUV) posted upbeat quarterly earnings. “We’re pleased. There was always concern the ECB would disappoint, so we’re pleased with size of the proposed actions, and the structure of it. There are moving parts, but overall it’s good news,” John De Clue, chief investment officer at the private client reserve at U.S. Bank Wealth Management.

ECB President Mario Draghi said the central bank would make monthly bond purchases of as much as $ 70 billion starting in March, and running through September of next year. Draghi’s announcement came after the ECB held benchmark rates unchanged at record lows. Southwest rose after the carrier posted quarterly earnings and revenue above estimates; Union Pacific (UNP) advanced after the railway reported a better-than-expected quarterly profit, and KeyCorp (KEY) jumped after the regional bank tallied fourth-quarter results that surpassed expectations. The CBOE Volatility Index (^VIX), one gauge of investor uncertainty, fell 14 percent to 16.16. After falling 71 points and jumping 286, the Dow Jones Industrial Average (Dow Jones Global Indexes: .DJI) was lately up 273.86 points, or 1.6 percent, at 17,828.14, with UnitedHealth Group (UNH) leading blue-chip gains that extended to 27 of 30 components. The S&P 500 (^GSPC) gained 30.69 points, or 1.5 percent, to 2,062.81, with financials leading sector gains and telecom faring the most poorly among its 10 major industries. The Nasdaq (^IXIC) rose 80.50 points, or 1.7 percent, to 4,747.09. For every share falling, four rose on the New York Stock Exchange, where 531 million shares traded as of 3:10 p.m. Eastern. Composite volume approached 3.1 billion. “It was telegraphed for so long that they were going to do something in terms of QE. Investors are skeptical about how effective QE is anyway. Our economy is doing better, but that’s because of the energy situation here; we own it,” Bruce Bittles, chief investment strategist at RW Baird, said. “Our economy didn’t respond to low interest rates and three rounds of quantitative easing, but it did respond to gasoline prices dropping by a third,” said Bittles, not an advocate of the Federal Reserve’s monetary policy. Thursday’s economic data had 307,000 Americans filing for jobless benefits last week, down 10,000 but more than the 300,000 forecast.

The U.S. dollar (Exchange:.DXY) rose against other global currencies, and the yield on the 10-year Treasury note (U.S.:US10Y) rose 2 basis points to 1.8951 percent. After rising above $ 49 a barrel early Thursday, the price of U.S. crude (New York Mercantile Exchange: @CL15H) fell 3.1 percent to $ 46.31 a barrel. Gold futures (CEC:Commodities Exchange Centre: @GC15G) rose $ 7.00, or 0.5 percent, to $ 1,300.70 an ounce. “Perhaps the worst in energy is behind us,” Dan Greenhaus, chief strategist at BTIG, wrote in emailed commentary, noting the sector has risen 5.2 percent in the last three sessions, and led Wall Street gains on Wednesday. On Wednesday, U.S. stocks advanced, with Wall Street’s volatility unabated, as investors largely adopted the view that the European Central Bank would implement a large-scale bond-purchasing program.

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