No tax imposed under this chapter shall exceed ten percent of the Massachusetts adjusted gross income less the aforementioned threshold; provided, however, that the provisions of this sentence shall not apply in any case where Massachusetts adjusted gross income exceeds one hundred and seventy-five hundredths of the aforementioned threshold. No exemptions shall be allowed under this section to a married individual filing a separate return, except for those individuals qualifying for head of household under section two (b) of the Code. In the case of a short taxable year, occurring for any reason other than residence during one portion of the normal taxable year and nonresidence during another portion, there shall be substituted for the above threshold amounts, those amounts which bear the same relation to such sums as the number of days in the taxable year bears to three hundred and sixty-five. With respect to a person who is a nonresident for all or part of the taxable year, Massachusetts adjusted gross income shall be determined as if he were a resident of the commonwealth throughout the entire taxable year.
Mass. Gen. Laws ch. 62, § 5