Allocation of certain nonbusiness income.

Rents and royalties from real or tangible personal property, capital gains, interest, dividends, or patent or copyright royalties, to the extent that they constitute nonbusiness income, shall be allocated as provided in Sections 6 through 9 [7-4-6 to 7-4-9 NMSA 1978] of the Uniform Division of Income for Tax Purposes Act.