Service tax computation

Madam, 

Thanks for your reply,

Can u Pls tell me ...how is the interest on S.tax Calculated ????And similarly how is Education Cess and Higer education Cess Affected. bcoz in April 15 and May 15, E.cess and HE cess were applicable. 

delay up to 6 month 18 % p.a

dealy from 6 month to 1 year 24 % pa.a

and delay for more than a year 30% p.a