A selloff in Monday afternoon trade reached levels that equate to panic-like levels. The Arms is a volume-weighted measure of market breadth, that tends to rise when the broader market falls, as the intensity of the selling in declining stocks is usually greater than the intensity of buying in rising stocks, was at 2.312 on the NYSE. Levels above 2.000 are considered panicky. The Dow Jones Industrial Average DJIA, -2.69% was down 540 points, or 2.2%, at 23,570 in Monday afternoon trade. The S&P 500 index SPX, -2.81% was down 2.9% at 2,564, trading below its 200-day moving average, while the Nasdaq Composite Index COMP, -3.17% turned negative for the year and for the session, off 3.2% at 6,838. The number of advancing stocks on the NYSE outnumbered decliners 2,368 to 536, or by around a 4.5-to-1 margin.