Now updated with the indecesive quarterback's latest unretirement.

In January 2006, Green Bay Packers quarterback Brett Favre said that if he "had to pick right now and make a decision, I'd say I'm not coming back." That was the first of five consecutive seasons in which Favre has insinuated, at one point or another, that he's going to stop playing football. Favre's 2010 faux retirement came on Tuesday, when reports surfaced that he texted his Minnesota Vikings teammates, "This is it." Less than 24 hours later, Favre told ESPN.com's Ed Werder that, of course, this isn't it—he'll play so long as his bum ankle doesn't fail him.

The quarterback's annual waffling—his most likely next moves: a tearful retirement press conference, followed immediately by a tearful unretirement press conference—have left fans and sportscasters confused and aghast. If you scrutinize the last three off-seasons, however, you'll learn that there's a method to Favre's seemingly random noodling. Introducing the Brett Favre Retirement Curve, an indispensible tool for analyzing and predicting the arc of the quarterback's yearly will-he-or-won't-he charade.

In the chart below, we have plotted key Favre news items from the 2008, 2009, and 2010 off-seasons, assigning each one a subjective indecision value. (Click the tabs at the top of the graphic to toggle between viewing each year independently and looking at all the data at once. You can also mouse over each point to read the associated headline.) We've then done our best to identify a pattern, sketching a curve that best fits each year's Favre-ian rollercoaster of hemming and hawing. As you'll see, each curve has at least two valleys—he's retiring!—and two peaks—he's coming back! Also notable: The endpoint of the Favre Retirement Curve has been creeping to the right each year, as the elderly QB takes longer and longer to make up his mind.

Update, Aug. 18, 2010: Wednesday's news that Favre is now practicing with the Minnesota Vikings brings the 2010 retirement curve to its logical endpoint. In the end, this year's graph looks remarkably similar to last year's version. So similar, in fact, that Favre's 2010 return comes on the exact same date, Aug. 18, on which he first signed with the Vikings in 2009.

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