Other methods of apportionment

(a) Where the methods provided in this Part do not apportion items of income, gain, loss and deduction in a fair and equitable manner, the Commissioner may require a nonresident individual to apportion those items under such method as the Commissioner prescribes, as long as the prescribed method results in a fair and equitable apportionment. In addition, a nonresident individual may submit an alternate method of apportionment with respect to items of income, gain, loss and deduction attributable to a business, trade, profession or occupation carried on partly within and partly without Connecticut. The proposed method shall be fully explained in the Connecticut nonresident income tax return. If the method proposed by such individual is approved by the Commissioner, it may be used in lieu of the applicable method described in this Part.

(b) The methods provided in this Part are presumed to result in fair and equitable apportionment, and any person, whether it be the Commissioner or a nonresident individual, proposing an alternate method of apportionment shall bear the burden of establishing that the methods provided in this Part unfairly and inequitably attribute items of income, gain, loss or deduction to Connecticut.