The Dow Jones Industrial Average is trading up Thursday morning with shares of UnitedHealth and Caterpillar seeing positive momentum for the blue-chip average. Shares of UnitedHealth UNH, +1.18% and Caterpillar CAT, +2.06% are contributing to the index’s intraday rally, as the Dow DJIA, +0.41% was most recently trading 140 points (0.4%) higher. UnitedHealth’s shares have gained $5.61 (1.3%) while those of Caterpillar have climbed $2.55, or 1.2%, combining for a roughly 54-point boost for the Dow. Other components contributing significantly to the gain include Apple Inc. AAPL, +1.18%, Chevron CVX, +2.52%, and Walgreens Boots WBA, +2.46%. A $1 move in any of the benchmark’s 30 components equates to a 6.58-point swing.