Shares of Boeing and Caterpillar are trading lower Wednesday afternoon, sending the Dow Jones Industrial Average into negative territory. The Dow DJIA, -0.96% was most recently trading 262 points (0.7%) lower, as shares of Boeing BA, -3.52% and Caterpillar CAT, -3.10% are contributing to the index’s intraday decline. Boeing’s shares have dropped $7.04, or 3.1%, while those of Caterpillar are off $6.86, or 3.0%, combining for an approximately 92-point drag on the Dow. American Express AXP, -2.88%, Goldman Sachs GS, -2.00%, and Apple Inc. AAPL, -2.10% are also contributing significantly to the decline. A $1 move in any one of the 30 components of the benchmark results in a 6.59-point swing.