How Likely Was An All One-Seed Final Four This March?

For just the second time since the advent of seeding for the NCAA Men's Basketball Tournament field in 1979, the Final Four is entirely made up of one-seeds. Auburn, Duke, Florida and Houston are all headed to San Antonio to compete for the title this year, defying tournament norms.

The only other time the Final Four was all one-seeds was back in 2008, when Kansas, Memphis, North Carolina and UCLA all made it (coincidentally, when the event was also in San Antonio). But how likely was that outcome this time?

• According to sports statistic guru (and former FiveThirtyEight analyst) Neil Paine, Duke had a 56% chance to make the Final Four, Auburn and Houston were 49% each, and Florida was 41% going into the tournament.
• While those figures sound pretty high (and they are), getting all four into the field still required three of them to buck the odds, even if slightly, and together, there was only a 5.5% chance that all four made it through before the event started (and theoretically that didn't change a ton since there weren't many upsets this year).
• At least early on, the chalk-filled brackets failed to deter TV audiences, as ratings climbed to three-decade highs (and seem likely to stay there since schools with major followings remained into the Sweet 16 and Elite 8 and games were closer in those rounds).