Oil prices are down, and stocks are up Monday, though such moves have been quick to reverse since the war in Iran began. The S&P 500 jumped 1.0 per cent and was on track for its best day in five weeks. The Dow Jones Industrial Average was up 379 points, or 0.8 per cent, as of 1:11 p.m. Eastern time, and the Nasdaq composite was 1.3 per cent higher.