The same burden of proof shall apply whether the corporation is petitioning for, or the director is requiring, the use of any reasonable method to effectuate an equitable allocation and apportionment of the corporation's income. Notwithstanding the previous sentence, if the director can show that in any two of the prior five tax years, the corporation had used an allocation or apportionment method at variance with its allocation or apportionment method or methods used for such other tax years, then the director shall not bear the burden of proof in imposing a different method pursuant to subdivision (2) of this subsection.
§ 143.455, RSMo