Dow falls 550 points, S&P 500 breaks below 4,000 as stocks head for worst day in nearly a month

U.S. stocks are on track for their worst daily pullback in nearly a month on Monday as the S&P 500 traded below 4,000. Equity prices have been rattled by stronger-than-expected economic data, which market strategists say could inspire the Federal Reserve to hike interest-rates more aggressively. The S&P 500
SPX,
-1.96%
fell 82 points, or 2%, to 3,988. The Dow Jones Industrial Average
DJIA,
-1.54%
fell 540 points, or 1.6%, to 33,889. The Nasdaq Composite
COMP,
-2.19%
fell 254 points, or 2.2%, to 11,206. All three indexes were on track for their worst day since at least Nov. 9, according to FactSet data. Meanwhile the Russell 2000
RUT,
-3.00%
was down 55 points, or 2.9%, to 1,837, on track for its biggest drop since Nov. 2.