Stories aren't the only thing high-profile studio anchors at CNN apparently know how to break. Judging by the latest TV ratings, they also seem to be succeeding in destroying the loyalty of viewers.
Figures from ratings agency Nielsen show America's most famous rolling news brand has just had its worst month for almost 20 years, parting company with more than 50 per cent of its audience in 12 months.
The development follows years of steady decline for the network, which pioneered 24-hour news in the 1980s, and was for years the top-rated news channel. In recent years, it has been hit by intense competition from Fox News and MSNBC, which now outperform it in almost every time slot.
The figures also raise questions about the future of Piers Morgan, hired to shake up its prime-time schedule with an hour-long weeknight interview show. He drew an average of 417,000 viewers, a fall of 50 per cent and the worst figure for the slot since the early 1990s.
Morgan's show is largely admired by critics. But his audience is volatile, and seems to vary according to the calibre of guests. Early last year, when he took over from octogenarian Larry King, who had about 600,000 viewers, Morgan said his show should be judged "by how we settle down" in six months to a year. By that measure, he's in trouble.