 This formula has made a tradition in conference play to keep track of how a team does against a particular region; and stats are kept as to how successful a team is against, for example, "the Bay Area schools" at home or away.Effective in the 2011–12 season, with the expansion into 12 teams, a 10-year rotation model has been developed to maintain the existing 18-game conference schedule.Teams remained paired with their regional rival.