One year ago, at the beginning of March 2011, the TV landscape—as far as the renewal prospects of scripted TV shows is concerned—was strikingly different. Although the number of cancelled TV shows was, oddly enough, identical to what we have today, there were already many more renewals. This season, it would seem, the major broadcast networks are not in a hurry to announce their decisions.
It is rather simple, really. The survival of a primetime scripted show generally depends on its average rating (in the adults aged 18-49 demographic) relative to the average rating of all other primetime shows on the same network. This means it is an intra-network affair, but also implies that, for a given show, retaining most of the audience of the show (in the timeslot) preceding it or even improving on that audience is not enough. What matters is how it performs compared to the network average. To put it in numbers, if your favorite show has a rating of 1.5 and the network average is 2.5, you have every reason to be worried. That is why for a network used to "good" ratings like CBS, posting an average of 2.0 in the 18-49 demo is not necessarily a guarantee of survival, while having a 1.0 rating on The CW is generally considered respectable.
Now, rules being what they are, there are exceptions to the above. Shows airing on Friday are often renewed with a much weaker average rating than others, which is not to mean moving a show to Friday bodes well for its renewal prospects. There is also the fact that even with ratings higher or on a par with its average, the network should consider its expectations. If the show is expensive to make, the network might have hoped for significantly higher ratings (which is in all likelihood the case for Fox's Terra Nova).
Another thing to consider is what image the network would like to project. It might want to stick with a show that wins Emmys or it might want to stop appearing like a network that always cancels all its rookie shows. So, out of the blue the network could renew one or two that do not necessarily perform well, or it might want to project that it rewards creativity by demonstrating "patience" with a show that is otherwise a "money pit." There is finally the possibility for a network to renegotiate a deal with the producers on production cost. Although these exception scenarios are always possible, they are far less likely to happen than a decision based on the average rating.
The prediction experts (tvbythenumbers.com, spoilertv.com, tvguide.com) have crunched the numbers, and although they do not always reach the same conclusions, it would appear shows like Alcatraz (Fox), A Gifted Man (CBS), and Fringe (Fox) are likely to be canceled. The Office (NBC), Person of Interest (CBS), and Grimm (NBC) are safe. Nikita (CW), and Supernatural (CW) could go either way. The full lists are much longer, obviously, but the point is that these predictions are based on ratings. On the blogosphere, some have already started making the case for those shows they feel might be in danger. There are for example talks about a shorter fifth season for Fringe to wrap up its story. Airing on Friday and boasting an abysmal average rating, Fringe is the quintessential exception to the rules based on ratings and many think that might help in the end, especially considering nothing has been announced yet.
