The QBR formula takes into account down, distance, field position, time remaining, rushing, passing sacks, fumbles, interceptions, how far each pass travels in the air, from where on the field the ball was thrown, yards after the catch, dropped balls, defensed balls, whether the quarterback was hit, whether he threw away the ball to avoid a sack, whether the pass was thrown accurately, etc. Each play carries "clutch weight" based on its importance to game outcome, as determined by analyzing those 60,000 plays since 2008. The stats adjust for quarterbacks facing an unusually high number of these situations.
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