Stocks boomeranged back up on Thursday after major tech companies reported better-than-expected earnings, breathing life back into Wall Street after a punishing start to the week.

The Dow Jones industrial average rocketed 401.13 points, or 1.6 percent, to 24,984.55 after losing 600 points on Wednesday. The surge pushed the index back into positive territory for the year.

Investors were roused from their bearish dens after Microsoft, Twitter and Tesla reported strong earnings, quelling pessimism that corporate profits have peaked following the Trump tax cuts in December.

“The financial conversation has been dominated by the outstanding performance and sexy character of tech stocks,” Jim Paulsen, chief investment strategist at Leuthold Group, said in a note.

That sentiment pushed the Nasdaq up nearly 3 percent, to 7,318.336 — a major turnaround from Wednesday, when the index had its worst day in seven years, falling 4.4 percent.

The S&P 500, a broader gauge of US stocks, saw a healthy bounce of nearly 2 percent, to 2,705.57.

Thursday’s surge, while a relief to some investors, comes after weeks of choppy markets.

October has been a wild month for stocks, sending volatility surging and causing bigger-than- average swings, as investors struggle to digest a mix of negative economic data and positive corporate earnings.

Escalating trade tension between the US and China, as well as soft housing sales data, has seeded much of the dour sentiment this earnings season, investors say.

“October has been the most volatile month since 1950,” Sam Stovall, chief investment strategist at CFRA, said in a note.