Oregon Revised Statutes Revenue and Taxation § 317.309

(1) To derive Oregon taxable income, there shall be added to federal taxable income the amount of any interest or dividends received during the taxable year from obligations of a state or any political subdivision of a state (including Oregon), exempt from federal taxation under the Internal Revenue Code. However, the amount added under this subsection shall be reduced by any interest on indebtedness incurred to carry the obligations or securities described in this subsection, and by any expenses incurred in the production of interest or dividend income described in this subsection.

(2) A regulated investment company as defined in section 851 of the Internal Revenue Code   1 which distributes dividends in excess of those deducted in the computation of federal taxable income, shall to the extent of the amount added under subsection (1) of this section, deduct such distributed excess in arriving at Oregon taxable income.

(3) To derive Oregon taxable income, and subject to the other provisions of this chapter, discount and gain or loss on retirement or disposition of obligations described under subsection (1) of this section issued on or after January 1, 1985, shall be treated in the same manner as under sections 1271 to 1283 and other pertinent sections of the Internal Revenue Code as if the obligations, although issued by a state or a political subdivision of a state, were not tax exempt under the Internal Revenue Code.