"Receipts" for the purposes of this rule covers revenue received by an operation during the period of its co-financing or during such longer period up to the closure of the assistance as may be fixed by the Member State, from sales, rentals, services, enrolment/fees or other equivalent receipts with the exception of:
(a) receipts generated throughout the economic lifetime of the co-financed investments and subject to the specific provisions of Article 29(4) of the General Regulation ...