(1) The APRC shall be calculated in accordance with the mathematical formula set out in Schedule 3.

(2) The costs of opening and maintaining a specific account, of using a means of payment for both transactions and drawdowns on that account and of other costs relating to payment transactions shall be included in the total cost of credit to the consumer whenever the opening or maintaining of an account is obligatory in order to obtain the credit or to obtain it on the terms and conditions marketed.

(3) The calculation of the APRC shall be based on the assumption that the credit agreement is to remain valid for the period agreed and that the creditor and the consumer will fulfil their obligations under the terms and by the dates specified in the credit agreement.

(4) In the case of credit agreements containing clauses allowing variations in the borrowing rate and, where applicable, in the charges contained in the APRC but unquantifiable at the time of calculation, the APRC shall be calculated on the assumption that the borrowing rate and other charges will remain fixed in relation to the level set at the conclusion of the contract.