Returns of affiliated groups of corporations

For tax years beginning before January 1, 2015, an affiliated group of corporations may file a consolidated return for the taxable year in lieu of separate returns; provided, that all the corporations which constitute the affiliated group at any time during the period for which the return is made and which are subject to taxation under this chapter shall consent to the making of the consolidated return. The tax administrator may prescribe rules and regulations as he or she may deem necessary in order that the tax liability of any affiliated group of corporations making a consolidated return and of each corporation in the group, liable to taxation under this chapter, both during and after the period of affiliation, may be determined, computed, assessed, collected, and adjusted in a manner as clearly to reflect the net income and the corporate excess and to prevent avoidance of tax liability.