Technically there would need to be three casualties to bring it back down to 13.
It is a fun history thinking through how we ended up here.
old Big Eight (Colorado, Iowa State, Kansas, Kansas State, Missouri, Nebraska, Oklahoma, Oklahoma State)
old Southwest refugees (Baylor, Texas, Texas A&M, Texas Tech)
8 + 4 = 12
Colorado bails for the PAC
Nebraska downgrades to the Big Ten
12 - 2 = 10
Texas A&M leaves and is more-or-less immediately replaced by TCU
Missouri leaves about the same time and is more-or-less immediately replaced by WVU
10 - 2 + 2 = 10
Texas and Oklahoma stab us in the back
call up the four best G5 programs to replace them (BYU, Cincinnati, Houston, and UCF)
10 + 4 = 14
Texas and Oklahoma actually depart
PAC falls apart
Big Ten raids the PAC for Southern Cal and UCLA and later Oregon and Washington
scoop up Arizona, Arizona State, Colorado, and Utah from the remnants
ACC desperately takes Cal and Stanford... poor Oregon State and Washington State
14 -2 + 4 = 16
So we've arrived at the current Big 12 of 16.
This map is not what I would have predicted during the initial Big 12 Missile Crisis...
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