(1) Each person issued an Idaho IFTA license as required under section 63-2438, Idaho Code, shall file with the commission in the manner and form prescribed by it, the tax report required by the IFTA. Such report shall contain a declaration by the person making the same, to the effect that the statements contained therein are true and are made under penalties of perjury, which declaration shall have the same force and effect as a verification of the report and shall be in lieu of such verification. The report shall show such information as the commission may reasonably require for the proper administration and enforcement of this chapter.
(2) The tax report shall be accompanied by the remittance covering the total tax, penalty and interest due. The tax due shall be calculated by multiplying the tax rate per gallon for each IFTA jurisdiction by the number of taxable gallons of fuel taxable in each IFTA jurisdiction, less any tax already paid upon purchases of fuel in that jurisdiction. The taxable gallons consumed shall be calculated by dividing the taxable miles traveled in each jurisdiction by such motor vehicles by the fleet average miles per gallon of such motor vehicles.