Bowl games originally featured the very best teams in college football, with strict bowl eligibility requirements for teams to receive an invitation to a bowl game in a particular year; as of 1971, there were only 10 team-competitive (as compared to all-star) bowl games. The number of bowl games has grown, reaching 20 games by the 1997 season, then rapidly expanding beyond 30 games by the 2006 season and 40 team-competitive games (not including the College Football Playoff National Championship) by the 2015 season. The increase in bowl games has necessitated a significant easing of the NCAA bowl eligibility rules, since reduced to allow teams with non-winning records (numerous teams since 2002 season) and even losing and seasons (10 teams since the 2001 season) to fill some of the many available bowl slots.