Assistance required in tds calculation for the new employee

Dear Sir/ Madam, I have one query regarding the the Tax exemption for the new employee joined on 15 th august 2013. I had calculated his total salary from previous employer and our company and gave deduction of 80 C,conveyance and HRA exemption for 6 months and also deducted Rs. 3000/- from tax liability recovered by the previous employer. , but as per sahil he also received HRA exemption in his previous company and medical bill reimbursement. That's why his tax is only Rs. 1000/- per month in the salary of Rs. 46620/- per month in the last company. So, how could we consider his HRA from previous company and medical bills which he had given in previous company in order to calculate the tax exemption now. Salary for our company : BASIC 31000.00 HRA 15500.00 MEDICAL 1250.00 CONVEYANCE 800.00 TPT ALLOWANCE 1600.00 SPECIAL ALLOWANCE 11850.00 TOTAL 62000.00