(1) Section 15-31-312, MCA, permits a departure from the allocation and apportionment provisions of 15-31-302 through 15-31-311, MCA, only in limited and specific cases.   Section 15-31-312, MCA, may be invoked only in specific cases where unusual fact situations (which ordinarily will be unique and nonrecurring) produce incongruous results under the apportionment and allocation provisions contained in 15-31-302 through 15-31-311, MCA.

(2) In the case of certain industries such as air transportation, rail transportation, ship transportation, trucking, television, radio, motion pictures, various types of professional athletics, and so forth, as the department deems necessary, the foregoing rules in respect to the apportionment formula do not set forth appropriate procedures for determining the apportionment factors.   Nothing in 15-31-312, MCA, or in ARM 42.26.261 through 42.26.263 shall preclude the department from establishing appropriate procedures under 15-31-306 through 15-31-311, MCA, for determining the apportionment factors for each such industry, but such procedures shall be applied uniformly.