Interest rate for non submission of c-form

Monica Balu Kharde (Senior Accountant) (79 Points)

30 January 2016  
One of my client made CST sales @ 2% in the year 12-13 & 13-14. Some of the parties fail to give C-forms. Sales are made outside Maharashtra & VAT applicability rate is 12.5%. Can anyone tell me how can i calculate Interest for that balance 10.5% liability.?