Jan 3 (Reuters) - U.S. stocks added to losses on Thursday after data showed factory activity in the United States slowed more than expected in December.
The Dow Jones Industrial Average fell 169.85 points, or 0.73 percent, at the open to 23,176.39. The S&P 500 opened lower by 18.11 points, or 0.72 percent, at 2,491.92. The Nasdaq Composite dropped 81.16 points, or 1.22 percent, to 6,584.77 at the opening bell. (Reporting by Sruthi Shankar in Bengaluru; Editing by Shounak Dasgupta)