If you're asking about the 5 tables (Rating Scores for the Bachelor's Degree Examination) then in each table, different rating is given for a range of percetage of a student's graduation degree. There are 5 tables each for Medical, Accouting, Engineering, Humanities and Economics. You need to look at the Annexure 1 to find out in which table your degree falls and how many points you will get according to the percentage you scored. 

Use this link for more clarity. 

https://www.iima.ac.in/web/pgp/apply/domestic/admission/selection-process