By Matt Egan, CNN Business

(CNN) -- The Dow jumped another 200 points, or 0.8%, on Monday. That follows Friday's 747-point spike.

All told, the Dow has surged more than 1,800 points since Christmas Eve. Not bad for a market that suffered its worst December since the Great Depression.

So what's driving the turnaround? Mostly it's cautious optimism about the trade war and health of the Chinese and American economies.

Investors are hopeful that the United States and China will reach a breakthrough on trade talks that began on Monday in Beijing. Wall Street has been worried that the trade clash is deepening slowdowns in both economies.

Friday's rally was set off by China's efforts to stimulate its economy as well as soothing words from Federal Reserve chief Jerome Powell, who promised patience while raising interest rates. And the blockbuster December jobs report has removed the fear of an imminent recession in the United States.