Formula For Conveyance Reimbursement

Dear All,
I work for a construction company where lot of staff are entitled for re-imbursment of conveyance on the basis of their official travel between different sites (local). Looking into the frequent changes in the petrol prices, we need to revise reimbursement rates too. My request to all of you to share some formula/basis on how to work out the correct re-imbursment rate/km for two wheeler and four wheelers.
Thanks
Ramesh

Hi.
I am an accountant in company ,I want to know how to calculate local conveyance for increase rate with new petrol rate of bike & car

Dear Sirs,
you can grade wise classified of the petrol conveyance
Rs.7/km if Rate is Rs. 80 to 90/ltr
Rs.6/Km if Rate is Rs 60 to 79/Ltr.
Etc.
I hope you can convince the seniors for the rate
regards
Niraj Kumar