The Dow Jones Industrial Average is declining Thursday afternoon with shares of Walgreens Boots and 3M facing the biggest setback for the blue-chip average. Shares of Walgreens Boots WBA, -2.99% and 3M MMM, -2.53% are contributing to the index’s intraday decline, as the Dow DJIA, -1.24% was most recently trading 239 points, or 0.7%, lower. Walgreens Boots’s shares have declined $1.14, or 2.3%, while those of 3M have declined $3.29 (1.8%), combining for a roughly 29-point drag on the Dow. Caterpillar CAT, -2.39%, Home Depot HD, -2.15%, and UnitedHealth UNH, -2.16% are also contributing significantly to the decline. A $1 move in any of the index’s 30 components equates to a 6.58-point swing.