5.—(1) Subject to section 24, for the purposes of this Act —
(a)
the benefits derived by any person from drug trafficking shall be any property or interest therein (including income accruing from such property or interest) held by the person at any time, whether before or after the commencement of this Act, being property or interest disproportionate to his known sources of income and the holding of which cannot be explained to the satisfaction of the court; and
(b)
the value of the benefits derived by him from drug trafficking shall be the aggregate of the values of the properties and interests therein referred to in paragraph (a).
(2) For the purpose of assessing the value of the benefits derived by the defendant from drug trafficking in a case where a confiscation order has previously been made against him, the court shall leave out of account any such benefits of drug trafficking or criminal conduct that are shown to the court to have been taken into account in determining the amount to be recovered under that order.