Whenever used in sections 12-81f, 12-81g, 12-81i, 12-81j and 12-81jj, “qualifying income” means, with respect to any person making application for exemption from property tax as provided under any of said sections, such person’s total adjusted gross income as determined for purposes of the federal income tax plus any other income not included in such adjusted gross income, individually if unmarried, or jointly with spouse if married, during the calendar year ending immediately preceding the filing of a claim for any such exemption, but does not include veterans’ disability payments. For purposes of determining eligibility for any of such exemptions, such qualifying income may not exceed fourteen thousand dollars, if unmarried, or sixteen thousand dollars, jointly with spouse, if married, provided in no event shall such maximum amounts of qualifying income with respect to any such person be less than the maximum amount of such qualifying income in the case of a married or unmarried person, whichever is applicable, under subsection (b) of section 12-170aa, and in the event that such maximum qualifying income under this section is less than the comparable amount under said subsection (b) of section 12-170aa for any assessment year, such amount under this section shall be made equivalent to that under said subsection (b) of section 12-170aa for purposes of determining eligibility under this section for such assessment year.