I want to use statistics to grade employee attendance/performance

Hi everyone,

I'm here to learn to apply statistics to my current problem - I need to translate raw data pertaining to employee attendance and performance at our various branches into something more succinct and palatable for my bosses.

My goal is to express the combination of two variables (attendance and performance) into a single percentage figure. each branch would ultimately get a grade AA,A,BB,B, etc.

I appreciate any help from anyone here.