Last year's fourth-quarter bear market went into overdrive due to several miscalculations by the Federal Reserve led by Jerome Powell, in which they underestimated the rapid decline in liquidity and the market's ability to handle further planned tightening for 2019. More fuel was added to the fire by rising escalations between the US and China regarding trade policy between the world's two largest economies.
After an official bear market in the S&P 500 of a greater-than-20% decline from the highs, the Fed adjusted its stance to a more neutral, market-friendly posture with Powell's early January