Performance Recovery across a wash is highly dependent on cycles, or deterioration, since the previous wash. For example, the more often an engine is washed, the lower every individual wash recovery will be; however a low recovery does not necessarily imply the wash was ineffective in this instance. The engine is just operating closer to optimal performance on a regular basis due to a healthy, regular wash program. The percent metric, therefore, relates recovery to the deterioration since last wash on a normalized basis. This often provides a more actionable and interpretable metric. Details of the calculation are available in the Tool Tips. If absolute recovery metrics are desired, they can be found within other pages of EWA.