Dear Sarin,

The computation of the value is like mentioned below,
invoice value multiplied by the exchange rate mentioned in the bayan. Then on the value you have to add the freight value if the shipment has come in FOB. Then on the subtotal you have to take 1% insurance, as the shipment as come from other country. If it has come from DUbai then there is an exemption in the insurance.
Now if u add the sub total + insurance then you get the CIF value, on which the 5% customs Duty is charged,
Now u will get the correct amount as per the Bayan.