Watch Now: Reid Forgrave reflects on one of the biggest upsets in sports history (1:08)

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If you're high-stepping around the living room and showboating about the CBS Sports bracket you claim is still perfectly intact, well, then chances are you're lying.

As of Friday evening there was only one perfect bracket remaining, and that bracketeer -- which had to sweat it out after No. 4 seed Auburn nearly tripped up against No. 13 seed College of Charleston in its Midwest Regional opener -- had theirs busted to pieces, thanks to the unexpected collapse of No. 1 overall seed Virginia.

There are now zero perfect brackets remaining with CBS Sports.

It's no surprise that most everyone's brackets are completely busted to smithereens. Such is the case every year -- hence the term March Madness.

The question is: Which first-round upset has busted your bracket -- and the brackets of others -- the hardest? We've got the data to answer that question, and hopefully you find comfort in the fact that you are not the only person on pace to lose your bracket pool.

No. 16 seed UMBC over No. 1 seed Virginia

You knew this one was going to top the list, didn't you?

No 16-seed had ever beaten a 1-seed in NCAA Tournament history before Friday, when the Retrievers annihilated the Cavaliers 74-54. The Cavaliers were not only a No. 1 seed, but the top overall seed in the NCAA Tournament before going one-and-done, making this the biggest bracket-buster not only for this season, but maybe ever.

A whopping 99.4 percent of brackets filled out through CBS Sports had Virginia advancing to the second round of the Big Dance -- second among all teams just a tick behind Villanova. And as the top overall seed, it should come as no surprise that Virginia was the top pick to win the championship, too.

Precisely 23.4 percent of all brackets had the Cavaliers cutting down the nets and winning it all, more than Villanova (20.9 percent), Duke (9.7 percent) and Michigan State (8.7 percent).

No. 13 seed Buffalo over No. 4 Arizona

No. 13 seed Buffalo downing No. 4 seed Arizona was a stunner in itself, but the fact that the Bulls did it in such resounding fashion - 89-68 -- only further muddles the waters of one of the weirdest results of the NCAA Tournament to date.

If you picked Buffalo in an upset here, you were in the minority. Exactly 92.8 percent of brackets submitted to CBS Sports had the Arizona Wildcats advancing to the second round, while 11.1 percent -- or seventh most among teams in the field -- pegged the Wildcats as a team that would end its season in the title game, with 4.2 percent picking them to win it all.

No. 13 seed Marshall over No. 4 seed Wichita State

Wichita State made its bones and brand over the last half-decade by evolving into a mid-major power prone to taking down major conference foes, and ironically, that exact scenario is why the Shockers are one-and-done in the Big Dance.

The Thundering Herd dispatched Wichita State 81-75, ushered in by a baffling replay whiff by the officials, and left the majority of the country grabbing for their red pen to mark out another bracket miss.

Exactly 90.3 percent of folks who submitted a CBS Sports bracket pegged the Shockers to advance into the second round -- 45.2 percent of whom also had them into the Sweet 16! -- leaving fans nearly as crippled as Arizona's shocker.

Only 5.9 percent had Wichita State advancing into the Elite Eight, and 0.3 percent had Gregg Marshall's team winning the whole thing.

No. 11 seed Loyola-Chicago over No. 6 seed Miami

Loyola Chicago delivered the first upset of the NCAA Tournament on Thursday, downing No. 6 seed Miami with a last-second 3-pointer at the buzzer as the go-ahead spoiler.

It was the Ramblers' first win in the NCAA Tournament in 33 years.

Not only was it the first upset of the Big Dance, but also the first true bracket-buster. Exactly 61.3 percent of people picked the Hurricanes to survive the Ramblers' storm, and 19.2 percent had them advancing into the Sweet 16. Only 38.7 percent picked Loyola-Chicago to win the game, and even fewer -- 9 percent, to be exact -- have them moving on to the 16.

No. 10 seed Butler over No. 7 seed Arkansas

A lot of metrics had Butler as a 7-seed and Arkansas as a team closer to a 10-seed, which made Butler over Arkansas one of the more picked 10-over-7 matchups in Round 1.

If you did so, you were spot on -- however, many others did not.

Precisely 34.2 percent of people picked Arkansas to win in the first round of the Tournament, while 6 percent had them advancing into the Sweet 16. Those numbers are 65.8 percent and 10.1 percent, respectively, for the still-alive Butler Bulldogs.