Helo Sourab

To be eligible for CLAT PG exams, the criteria is

• An LLB degree or equivalent examination with a minimum of 55% of marks or equivalent grade in case of candiate belong to General/OBC/PWD/NRI/PIO/OCI categories and 50% marks or equivalent grade in case for SC/ST canditates
• Canditate appearing in qualifing examination are also eligible to apply
• there is no upper age limit prescribed for CLAT2019

i am assuming that you are general candidate based on you query

So to be eligible to apply you have to score an aggregate of 55% of all 5 years   

Hope this will be helpful