How To Calculate PF Amount?

Dear All,
Any one help me how to calculate PF maturity.
I Know the PF interest is 8.5 %, But i want to know about the interest rate calculation.
Please tell me,whether the interest rate will be calculate monthly basis or yearly basis..?
Please explain to me an example or case study....

Dear ashok
PF interest will be calculated one the closing balnce as on 31/mar/2013.
Regards
Prasad

as and when employee resigned in the mid of the year on prorate basis the interest will be calculated.

on his/her date of withdrawal!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!