8. (1) An authorised distributor shall, not later than 31 March in each year, lodge with the Commissioner a return in relation to the immediately preceding calendar year.
(2) A return shall be in writing, in a form approved by the Commissioner, and shall specify—
(a) the quantity of gas sold by the authorised distributor during the immediately preceding calendar year; and
(b) the gross revenue derived by the authorised distributor in respect of the sale of gas during that year.