Even the best television shows run out of creative juice if they stay on the air long enough. But, when is the right time to give up hope a show will improve and abandon it forever? Finally, a handy calculation!

We have a tendency to remain faithful to our favorite shows for far too long. When they start to take a turn for the worse, we hold out hope that they will get smart and return to their former glory. We wait and we wait and no improvement comes, and then we feel like we have to see it to the end, now that we've invested so much time in waiting for it to get good, we don't want to leave and have it return to form without us.

We were seized with this dilemma last night while watching Desperate Housewives. And before you start joking, Housewives in it's first season was awesome. It was fresh, funny, campy, and full of unexpected joy. It took a turn for the worse in seasons two and three, but rebounded in seasons four and five. Now we're well into the show's sixth year, and while it is still highly rated, it isn't what it used to be creatively. There are tons of peripheral characters that we barely care about, Teri Hatcher's Susan is even more unlikable than ever, Felicity Huffman's Lynette is pregnant again, and the writers even managed to make Eva Longoria Parker's reliably hilarious Gaby a snooze while seriously underusing the fantastic Dana Delany and Drea de Matteo. The show has gotten so bad, in fact, that we no longer enjoy making jokes about what a shitty mother Susan is or how annoying we find her daughter, Julie.

That is when it struck us—there is actually a formula that we can use to figure out when to quit watching a show, and it looks something like this:

We estimate that each season is worth 8 months, and that "joy" is measured on a sliding scale of 0-5, with zero being no jokes at all and 5 being Gossip Girl levels of hilarity at its badness (really, "Serena is a skank" jokes never get stale). So, if you plug the numbers in for Desperate Housewives here is what happens:

120 - 56 / 0 = 0

That means no more time should be afforded Desperate Housewives. Fine by us! Consider your season pass deleted from our TiVo.

This also works for deciding what to do about a new show. Here is our calculation for V, which we still find moderately amusing because of the aliens wearing human skin concept, but is starting to wear on us. Since it's a newer show, we calculated in weeks rather than months:

4 - 2 / 1 = 2 episodes.

Alright, V, you have two episodes to prove yourself when you return in March. If you can impress us in that window, then we'll keep you around until you start smelling worse than an giant alien ship without a sewage disposal and we have to bust out our formula again to calculate your life span.

But, like most formulas, there is a variable, and that is what else is on at the same time. Right now, there isn't much in terms of television greatness on Sunday nights until Big Love returns January 10, which means Housewives may get a stay of execution until then. But as soon as it does, mathematics has determined that the ax will fall. And we won't even feel guilty about it, now that we have our patented Television Doomsday Clock and good old algebra on our side.

[Image via EssG's Flickr]