R.I. Gen. Laws § 44-13-5 — Deductions for merchandise sales and alternative fuel

(a) In the case of every corporation whose principal business is manufacturing, selling,
and distributing to the public illuminating or heating gas, and upon which a tax is
imposed under § 44-13-4(5), and in the case of every corporation upon which a tax is imposed under § 44-13-4(2), there shall be allowed as a deduction from the gross earnings from merchandise sales
reported by that corporation in its gross earnings tax returns, the net invoice price
plus the transportation cost of the merchandise.
(b) In the case of every corporation upon which a tax is imposed under § 44-13-4 there shall be allowed as a deduction from the gross earnings from sales reported
by the corporation in its gross earnings tax returns, the total of gross earnings
from the sale of alternative fuel as defined pursuant to the Energy Policy Act of
1992 (P.L. 102-486, Section 301 (42 U.S.C. § 13211)) when used as a separately metered motor fuel that powers a motor vehicle, from
January 1, 1998, until December 31, 2007.