Question: The 2001 Colorado Buffaloes football team played in the playoff game that was first played during what stretch of years?

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List of Colorado Buffaloes head football coaches: The Colorado Buffaloes football program represents the University of Colorado Boulder in the Pac-12 Conference South Division of the National Collegiate Athletic Association.  The team has had 25 head coaches since it started playing organized football in 1890.  The university adopted the nickname "Buffaloes" in 1934 after previously being known as the "Silver and Gold", "Silver Helmets", "Yellow Jackets", "Hornets", "Arapahoes", "Big Horns", "Grizzlies" and "Frontiersmen".  Colorado played without a head coach during their first four years.  The team first joined a conference in 1893 when they became a member of the Colorado Football Association.  They joined the Colorado Faculty Athletic Conference in 1909, immediately followed by the Rocky Mountain Athletic Conference in 1910.  Before the 1938 season, Colorado joined the Mountain States (Skyline) Conference.  They joined the Big Seven Conference in 1948, which was renamed the Big Eight Conference in 1958 when Oklahoma State joined/rejoined the Conference.  The Buffaloes became a charter member of the Big 12 in 1996 when the Big Eight disbanded.  The Buffaloes have played in 1,139 games during their 120 seasons.  In those seasons, nine coaches have led Colorado to postseason bowl games: Bunny Oakes, Dallas Ward, Bud Davis, Eddie Crowder, Bill Mallory, Bill McCartney, Rick Neuheisel, Gary Barnett, and Dan Hawkins.  Nine coaches have won conference championships with the Buffaloes: Fred Folsom, Myron Witham, William Saunders, Oakes, Jim Yeager, Sonny Grandelius, Mallory, McCartney, and Barnett.

2010 Colorado Buffaloes football team: The 2010 Colorado Buffaloes football team represented the University of Colorado in the 2010 NCAA Division I FBS football season.  The team was coached by fifth-year head coach Dan Hawkins for the first nine games and interim head coach Brian Cabral for the final three games.  Colorado played their homes game at Folsom Field.  It was also the final season as members the Big 12 Conference in the North Division for Colorado, before joining the Pac-12 Conference for the 2011 season.  The Buffaloes failed to qualify for a bowl game, as they finished the season 5–7, 2–6 in Big 12 play.

1975 Colorado Buffaloes football team: The 1975 Colorado Buffaloes football team was an American football team that represented the University of Colorado at Boulder in the Big Eight Conference (Big 8) during the 1975 NCAA Division I football season.  In their second season under head coach Bill Mallory, the Buffaloes compiled a 9–3 record (5–2 against Big 8 opponents), finished in third place in the Big 8, and outscored their opponents, 331 to 251.  The team played its home games at Folsom Field in Boulder, Colorado.

2005 Colorado Buffaloes football team: The 2005 Colorado Buffaloes football team represented the University of Colorado at Boulder in the 2005 NCAA Division I-A football season.  The previous year's team won the Big 12 North Conference.  That marked the third Big 12 North championship for the Buffaloes in four years.  The team had expectations to improve on their winning and appeared to be on the right track with a 7–2 record to begin the season.  But in the end, head coach Gary Barnett had his contract bought out and Colorado suffered four straight losses including an embarrassing 70–3 loss to Texas in the Big 12 Championship Game.  They finished the season 7–6.  In the 2005 Champs Sports Bowl against Clemson, Mike Hankwitz acted as interim head coach, even though Dan Hawkins had been hired as the new head coach.  Hawkins coached his final game with Boise State in the game the day after Colorado played.

2012 Colorado Buffaloes football team: The 2012 Colorado Buffaloes football team represented the University of Colorado Boulder during the 2012 NCAA Division I FBS football season.  Led by second-year head coach and alumnus Jon Embree, the Buffaloes played their home games on-campus at Folsom Field in Boulder and were members of the Pac-12 Conference.  On November 25, 2012, head coach Jon Embree was fired after compiling a 4–21 record including 1–11 in his final year, the worst year in the history of Colorado Buffaloes football.

Big 12 Championship Game: The Big 12 Championship Game is a college football game held by the Big 12 Conference.  The game was played each year since the conference's formation in 1996 until 2010 and will return starting with the 2017 season.  From 1996 to 2010 the championship game pitted the Big 12 North Division champion against the South Division champion in a game held after the regular season was completed.  From 2017 onward, the game will feature the two teams with the best records within the conference.

2002 Colorado Buffaloes football team: The 2002 Colorado Buffaloes football team represented the University of Colorado at Boulder during the 2002 NCAA Division I-A football season.  The team played their home games at Folsom Field in Boulder, Colorado.  They participated in the Big 12 Conference in the North Division.  They were coached by head coach Gary Barnett.  Colorado played in the Big 12 Championship Game for the second time, but lost to Oklahoma.

1976 Colorado Buffaloes football team: The 1976 Colorado Buffaloes football team represented the University of Colorado at Boulder in the Big Eight Conference (Big 8) during the 1976 NCAA Division I football season.  In their third season under head coach Bill Mallory, the Buffaloes compiled an 8–4 record (5–2 against Big 8 opponents), finished in a three-way tie for the Big 8 championship, and outscored their opponents, 305 to 225.  The team played its home games at Folsom Field in Boulder, Colorado.

1974 Colorado Buffaloes football team: The 1974 Colorado Buffaloes football team was an American football team that represented the University of Colorado at Boulder in the Big Eight Conference (Big 8) during the 1974 NCAA Division I football season.  In their first season under head coach Bill Mallory, the Buffaloes compiled a 5–6 record (3–4 against Big 8 opponents), finished in fifth place in the Big 8, and were outscored by their opponents, 307 to 226.  The team played its home games at Folsom Field in Boulder, Colorado.

2001 Colorado Buffaloes football team: The 2001 Colorado Buffaloes football team represented the University of Colorado at Boulder during the 2001 NCAA Division I-A football season.  The team played their home games at Folsom Field in Boulder, Colorado.  They participated in the Big 12 Conference in the North Division.  They were coached by head coach Gary Barnett.  Colorado played in the Big 12 Championship Game for the first time and secured its first BCS bowl berth.

Supporting paragraphs: 2001 Colorado Buffaloes football team Big 12 Championship Game
Answer: 1996 until 2010