The NCAA tournament expanded from 48 teams to 64 in 1985 and increased to the current 65 teams in 2001. There are some who propose increasing the number to 96, but the NCAA tournament committee is not considering that option at this time.
64 teams in the NCAA tournament in 2000
4 2012
1985
Michigan State did not make the NCAA tournament in 1980 after winning the championship in 1979. Florida did not make the NCAA tournament in 2008 after winning the 2007 championship. North Carolina won the NCAA tournament in 2009 and will not make the tournament in 2010.
64
In 2013, assuming that's what you mean by "this year," the NCAA Men's basketball tournament included teams from 31 states and the District of Columbia.
1. University of Illinois - Urbana Champaign
The first NCAA Basketball Tournament was held in 1939.
Technically only 64 teams are in the tournament, but 2 teams play for the 64th spot, so you could also say 65.
1939 1939
Yes there have been a total of 20 teams that won the tournament and then did not make it the next year. Since the tournament expanded to 64 teams in 1985 there have been 5 teams to not make it back the next year. Louisville 1987 Kansas 1989 Florida 2008 North Carolina 2010 Kentucky 2013
The Wisonsin Badgers played in the 2010 NCAA Men's Basketball Tournament.