The employee performance appraisal system we use in our organisation is the KPI type. Its a spreadsheet format which contains weighting allocation, rating and scale which are used to calculate the KPI of employees. I've tried to modify the_hr appraisal module to include the KPI with the corresponding weighting allocation,rating and scale but i couldn't find a  way to compute these  numbers.  Is there  a way to do this  or i will  have to  create a  custom module? Thanks