The S&P 500 added 0.4% on Thursday, Jan. 30, as a report showed consumer spending continued to buoy economic growth.

Comcast, led by chairman and CEO Brian Roberts, reported fourth-quarter and full-year results for its entertainment unit and other operations.

But shares of the media conglomerate fell over 12% on Thursday after it shed a worse-than-expected 139,000 domestic broadband customers. Comcast Cable president and CEO Dave Watson previously warned ...