A. A taxpayer may claim a deduction from net income in an amount equal to the greater of:
(1) the taxpayer's net capital gain income for the taxable year for which the deduction is being claimed, but not to exceed two thousand five hundred dollars ($2,500); or
(2) forty percent of up to one million dollars ($1,000,000) of the taxpayer's net capital gain income from the sale of a business that is allocated or apportioned to New Mexico pursuant to Section 7-2-11 NMSA 1978 for the taxable year for which the deduction is being claimed.
B. Married individuals who file separate returns for a taxable year in which they could have filed a joint return may each claim only one-half of the deduction provided by this section that would have been allowed on the joint return.
C. As used in this section, "net capital gain" means "net capital gain" as defined in Section 1222 (11) of the Internal Revenue Code.