“If there was one over-arching principle for analyzing soccer statistics, it might be “context is king.” For example, Arsenal’s Bacary Sagna averaged 54.5 passes per 90 last year and West Ham’s Mark Noble averaged 53.2 passes per 90. Intuitively, our first reaction is probably that both players exhibit roughly the same level of passing influence—with maybe the slightest of edges given to Sagna. But we are not controlling for the fact that Arsenal led the EPL with 569 passes per game while West Ham was second from bottom, averaging 326 passes per game. To adjust for this disparity we take each player’s passes per 90 and divide it by their team’s passes per 90, thereby creating a pass usage rate for each player.” Statsbomb