Charter Communications, the nation’s third biggest cable television system operator, is having a tough time coming out of a nosedive. The company says its fourth-quarter was $340 million, and co-chief financial officer, Derek Chang is quitting. Charter, has been so badly mismanaged that one wonders what’s going on with this company. In a quarter when every rival added digital video customers, Charter lost 14,200. And then there is the executive turmoil. Chang is the latest to exit Charter, following chief executive and president Carl Vogel who resigned in January. The same month, chief administrative officer Steven Schumm said adios to the company as well. The good news _ internet data revenues were up $53 million, or 35%, compared to the pro forma year ago quarter to $203 million. The company has 1.884 million internet users.