EPA Success Rate explained | Next Gen Stats

Football games are decided by points scored, but per-play performance is also crucial. Traditional methods of judging offenses and defenses by yards gained or allowed are flawed. Next Gen Stats, powered by AWS, uses two additional metrics: Expected Points Added (EPA) and Success Rate. Expected Points measures a team's likely score at any given time, and EPA quantifies how this number changes per play. EPA helps contextualize yardage importance; for example, six yards on third and five is more valuable than on third and fifteen. Elite offenses average around 0.1 EPA per play. This metric can be segmented to analyze individual player contributions, like a quarterback's EPA per dropback, with elite quarterbacks averaging 0.2 EPA per dropback. Success Rate, another metric, uses EPA to determine if a play increased a team's scoring chances. A positive EPA signifies a successful play, while a negative EPA indicates an unsuccessful one. Elite offenses achieve a success rate of just under 50%. Both EPA and Success Rate measure offensive efficiency differently. EPA accounts for explosive positive and negative plays like turnovers, whereas Success Rate weights every play equally. EPA per play offers an overall unit picture, while Success Rate emphasizes consistency. Understanding what each metric captures is vital for proper use.