The interest rate to be applied shall be the rate applicable on the date on which unlawful aid was first put at the disposal of the beneficiary.

The interest rate shall be applied on a compound basis until the date of the recovery of the aid. The interest accruing in the previous year shall be subject to interest in each subsequent year.

The interest rate referred to in paragraph 1 shall be applied throughout the whole period until the date of recovery. However, if more than one year has elapsed between the date on which the unlawful aid was first put at the disposal of the beneficiary and the date of the recovery of the aid, the interest rate shall be recalculated at yearly intervals, taking as a basis the rate in force at the time of recalculation.