(1) If a corporation changes its taxable year in accordance with Section 59-7-502, a short period return shall be made for the period of less than 12 months between the close of the last taxable year for which a return was made and the close of the new taxable year.

(2) Where a short period return is made under Subsection (1) on account of a change in the accounting period, and in any other case where a short period return is required or permitted by rules prescribed by the commission to be made for a fractional part of a year, the tax shall be calculated at the rate provided in Section 59-7-104 for the period covered by the return assignable to business done in Utah.