Behind strong returns for shares of Merck and Walt Disney, the Dow Jones Industrial Average is rallying Friday afternoon. Shares of Merck MRK, +8.69% and Walt Disney DIS, +4.25% are contributing to the index’s intraday rally, as the Dow DJIA, +1.49% is trading 493 points, or 1.5%, higher. Merck’s shares are up $7.53 (10.0%) while those of Walt Disney are up $7.56, or 4.5%, combining for an approximately 99-point boost for the Dow. Also contributing significantly to the gain are American Express AXP, +4.09%, IBM IBM, +3.13%, and Visa V, +3.49%. A $1 move in any of the Dow’s 30 components equates to a 6.58-point swing.