NEW YORK (AP) — U.S. stocks dove Tuesday following another stunning reversal, with Wall Street veering from a huge gain at the opening of trading to more losses at the close, because investors still have no idea what to make of President Donald Trump’s trade war, which is scheduled to kick into a higher gear after midnight.

After blasting to an early gain of 4.1%, which would have marked its best day in years, the S&P 500 quickly lost all of it. It then careened to a loss of 3% before paring its drop to 1.6%. That left the index, which sits at the heart of many investors’ 401(k) accounts, nearly 19% below its record set in February.

The Dow Jones Industrial Average lost 320 points, or 0.8%, after erasing an earlier surge of 1,460 points, while the Nasdaq composite dropped 2.1%.

The shocking swings followed rallies for stocks globally earlier in the day, with indexes up 6% in Tokyo, 2.5% in Paris and 1.6% in Shanghai.