Sprint Corp. reported 1999 net income of $1.57 billion, up 2%, on revenue of $17.02 billion, up 8%. Fourth-quarter net was $416 million, up 3%; revenue, $4.41 billion, up 8%. It cited Sprint Nickel Nights promotions for double-digit gains in residential long-distance calling volume; more than 1 million residential long-distance accounts were sold in 1999 through its Radio Shack tie-in. Its Sprint PCS wireless service added 1 million-plus subscribers in the fourth quarter. In trading Friday, Sprint closed at $60.50, up 0.42% for the week.