There are 2 types of product management broadly - New Product and Existing products. For an existing product, the task of the product manager is to increase revenue, in a declining market share scenario arrest/protect the revenue from further decline. Find ways for cost reduction.
Is there a way to collectively look at the performance of the PM by looking at the aforementioned indicators and other metrics and condense them into a single composite variable or index of sorts.
Such that when one looks at the number, depending on the magnitude one can say the PM has done his job well, moderately well, or has performed poorly.