Shares of Microsoft and Salesforce.com Inc. are trading lower Tuesday morning, dragging the Dow Jones Industrial Average into negative territory. Shares of Microsoft MSFT, -2.10% and Salesforce.com Inc. CRM, -1.98% have contributed to the blue-chip gauge’s intraday decline, as the Dow DJIA, -0.57% was most recently trading 141 points (0.4%) lower. Microsoft’s shares are down $6.02 (2.1%) while those of Salesforce.com Inc. are off $4.92 (1.8%), combining for an approximately 72-point drag on the Dow. Also contributing significantly to the decline are Visa V, -1.44%, Walt Disney DIS, -1.24%, and Apple Inc. AAPL, -1.00%. A $1 move in any one of the 30 components of the index equates to a 6.58-point swing.