In gridiron football, a safety (or safety touch) is a scoring play worth two points, awarded when the ball carrier is tackled in their own end zone, the ball becomes dead there, or the offense commits a foul in that area. After a safety, the scored-upon team must kick off from its 20-yard line in American football, whereas in Canadian football, the scoring team can choose to take possession at its 35-yard line, kick off from there, or accept a kickoff from the opponent. Despite its low point value, a safety carries significant strategic weight—analyst Brian Burke estimated it has greater abstract value than a field goal due to the reclaimed possession and favorable field position gained from the ensuing kick. Safeties are the least common scoring method in American football, occurring roughly once every 14 games in NFL history (about once a week), but they are far more common than the one-point (conversion) safety. This rare one-point safety, scored on extra-point or two-point conversion attempts, has occurred only twice in NCAA Division I since 1996 (most recently at the 2013 Fiesta Bowl) and hasn't happened in the NFL since 1940. A conversion safety by the defense has never occurred, but it remains the only theoretical way a team could finish a game with exactly one point.