Bonus data! Download this sortable spreadsheet showing the performance of every man who's ever tossed a pass in Super Bowl play.)
A version of this story originally ran in February 2006, before Super Bowl XL. We've updated it before each Super Bowl since.
This Bloodbath of Data highlights the performances of every quarterback who (and this is key, folks) appeared in more than one Super Bowl. So if you're wondering why Ken Stabler or Steve Young is not on the list, that's why.
The big news this year is that New England quarterback Tom Brady has been demoted from Super Bowl Legend to Super Bowl Champion.
Patriots fans can bitch and moan, but the logic behind the demotion is unassailable:
One - All the Legends on the list (Montana, Plunkett, Bradshaw, Aikman and Starr) are undefeated in Super Bowl play. And, in case you hadn't heard, Brady is no longer undefeated in Super Bowl play.
Two - Not so coincidentally, the five Legends also boast the five best Super Bowl passer ratings of all the quarterbacks who have appeared in multiple Super Bowls. Gee, what a coincidence: guys that pass most effectively win the most Super Bowls. Who'd a thunk it?
Not so coincidentally, when Brady was among the six undefeated Super Bowl quarterbacks, he was among the six best in cumulative Super Bowl passer rating. No more! After the loss to the Giants last year, Brady tumbled below both Roger Stauback and (yikes!!) Brett Favre on the list of Champions. (For the record, the QBs are basically listed by order of passer rating).
Sure, the Giants made life difficult for Brady, Patriots fans. But, to paraphrase a certain coach, the numbers are what the numbers are. If you want Brady to remain among the legends, we suggest a visit to Warm, Cuddly Pigskin
The best part is that we'll see one Champion, Kurt Warner, in action in Super Bowl XLIII and we'll see another player, Ben Roethlisberger, gearing up for his second Super Bowl earn a place somewhere on this list. Whether he's a Cling-On or a Champion remains to be seen.
The original story appears below, complete with our gratuitous Patrick Swayze reference.
The Bloodbath of Data
(text is from last year)
We treat quarterback statistics much the way we were treated as towel boys for the Honky Tonk University football team: We toss them out windows, kick them through doorways and smash their heads through the jukebox of gridiron analysis, leaving the soundtrack of our sorry existence an endless loop of scratchy Merle Haggard and Toby Keith recordings.
Our outlaw lifestyle has its benefits: The data always reveal their secrets after they've been beaten into submission by our gridiron Dalton in the Double Deuce roadhouse of pigskin punditry.
This week, our daily little barroom brawl with the data has turned into a complete bloodbath as we considered the topic of the greatest Super Bowl quarterbacks of all time. After kicking and a-gouging in the mud and the blood and the beer, the data is just oozing out onto page upon page of information about the best and worst quarterbacks in Super Bowl history.
Why expend so much effort? Well, quarterbacks are the single most important players on the field, and it's their performances that hold the key to Super Bowl success. Tom Brady and Eli Manning will not step on the field against each other in Super Bowl XLII, but the battle between the two is the most important encounter in the biggest game of the year.
By the end of the game, Brady may secure his position among the most elite of all football players: the legendary Super Bowl quarterbacks. Or  he might find that legend took a mighty hit. With a poor performance and a loss, Manning might be asked if he has what it takes "to win the big game," a question often asked of our Super Bowl Cling-Ons and the crippled, hunchbacked Gimps who repeatedly rang the bell of Super Bowl failure. Even those Champions who enjoyed some semblance of Super Bowl success were often doubted in their Super Bowl careers.
So here's what we did: We looked at every quarterback who has played in at least two Super Bowls, rated them from top to bottom and then placed them in one of four different categories. Essentially, these are ranked top to bottom based upon Super Bowl passer rating. But it all works out so neatly: the six guys who qualify as "Super Bowl Legends" have the six highest passer ratings (among those who made multiple appearances) and, not so coincidentally, are a perfect 18-0 in Super Bowl play.
Montana, Plunkett, Bradshaw, Aikman, Starr & Brady: These are quarterbacks who played well and won every time they appeared in the big game. They've won nearly half (18) of all the Super Bowls played (41).  
Favre, Staubach, Warner & Dawson: These are quarterbacks who played well in Super Bowl victory and not so well in Super Bowl defeat. 
Griese, Elway & Theismann: These are quarterbacks who won Super Bowls, but who owe much of their Super Bowl success to great running games.  
Kelly, Tarkenton, Unitas, Morral & Morton: These guys played like gimpy hunchbacks in their Super Bowl appearances.
The NFL requires 40 pass attempts to be considered for the Super Bowl record books. But our method – QBs who appeared in two or more games – is actually a more inclusive and accurate way to measure Super Bowl success. First and foremost, our method includes a handful of quarterbacks who appeared in more than one Super Bowl but who did not attempt 40 or more passes.
Both methods eliminate one-hit wonders like Phil Simms in Super Bowl XXI and Steve Young in Super Bowl XXIX. But our method also eliminates Super Bowl duds like Rich Gannon, who, in his one Super Bowl appearance, attempted 44 passes but was picked off 5 times. (You can compare the performances of all Super Bowl passers in our sortable spreadsheet.)
It's unlikely Simms or Young could replicate their record-setting performances in another Super Bowl appearance. It's also hard to believe that Gannon would be equally as awful if he had another Super Bowl shot. And it's simply not fair to compare these one-game performances against quarterbacks who have played in as many as three, four or five Super Bowls.
Clearly, the multi-game body of work of the quarterbacks on our list gives us a more even playing field of analysis.
Here, then, is our look at the first-to-worst Super Bowl quarterbacks, from a legendary Joe Montana to a gimpy Craig Morton.

The Legends 

The Champions 

The Cling-Ons

The Gimps