Walton is right. It's too easy to slip into talking about CNN as if it's only CNN/U.S. It's more complicated to talk about the entire CNN News Group and harder to compare, because, really, who can compete with that? There is no other collection of news networks out there. It's also tempting to pare the comparison down to a CNN-Fox matchup because of the schoolyard snubs involved, the bloody numbers, and the backhanded compliments. You know the ones, spoken with a tone of false modesty: "They're very good at what they do, and we're very good at what we do."

So let's just get it out of the way. CNN/U.S.'s ratings may have spiked during the tsunami, but the network was still trounced by Fox, which drew 1.5 million viewers nightly to CNN's 934,000. And after the spike, the ratings fell precipitously for both networks.

This is how cable news works in the U.S., according to Andrew Tyndall, a media analyst who cowrote a report on American broadcast news for the Project for Excellence in Journalism. Ratings sprint upward during a big news event and plummet just as quickly afterward. Sometimes, a cable news network holds on to a portion of the viewers it gained during the spike, but even then the gains are small. Median viewership offers a better year-over-year comparison, and those numbers show CNN's audience declined by a couple of percentage points from 2003 to 2004, at a time when Fox News's audience was growing.

But as any statistician knows, numbers can be sliced and diced many different ways, and some of those make CNN look better. The network seems to do well with younger people - the 18- to 49-year-old crowd popular with advertisers - and with people who want their news whenever they happen to feel like watching, rather than at a particular time of day. Tyndall calls these viewers the news-on-demand audience, and their checking in with CNN for short bursts of news helped the network rack up some 64 million unique viewers each month of 2004, compared with 56 million at Fox. On Election Day alone, CNN attracted 38 million viewers, compared with Fox's 32 million.