So if 8 Big 12 teams and 7 Big East teams advanced. That means almost half the remaining field is made up from 2 conferences. (15 of 32 ~ 47%)
The Big 12 made a little NCAA tournament history on Saturday and Sunday, becoming the first conference in Division I history to go 8-0 in first-round games.
The Big East nearly equaled the feat, going 7-1 (Hartford upset seventh-seeded Syracuse on Saturday). In fact, the Big East was 7-1 in the first round last season, as well.
A look at how other leagues fared in the first round after placing eight teams in the field of 64:
2004: Big East 5-3
2002: SEC 6-2
1999: SEC 6-2