(4) “Chief Financial Officer” means the Chief Financial Officer of the District of Columbia.
(5) “District gross receipts” means all income derived from any activity whatsoever from sources within the District, other than income of a feepayer derived from an ownership or beneficial interest in other feepayers subject to the ballpark fee, whether compensated in the District or not, prior to the deduction of any expense whatsoever connected with the production of the income, provided, that the calculation of the income shall not include:
(A) The collection of federal or local taxes on motor vehicle fuel; or
(B) Fees retained by a retail establishment under [§ 8-102.03(b)(1)].
(6) “Feepayer” means any person, fiduciary, partnership, unincorporated business, association, corporation, or any other entity subject to:
(A) Subchapter VII of Chapter 18 [of this title];
(B) Subchapter VIII of Chapter 18 [of this title]; or
(C) Chapter 1 of Title 51 of the District of Columbia Official Code, except any employer in the employer’s capacity as a householder as distinguished from an employer in the pursuit of a trade, occupation, profession, enterprise, or vocation.