Consolidated statements.

For the purpose of this chapter, whenever a corporation which is required to file an income or franchise tax return is affiliated with or related to any other corporation through stock ownership by the same interests or as parent or subsidiary corporations, or whose income is regulated through contract or other arrangement, the department may require such consolidated statements as in its opinion are necessary in order to determine the taxable income received by any one of the affiliated or related corporations or to determine whether the corporations are a unitary business.