In determining whether indebtedness for transit purposes may be excluded under this paragraph of this section, there shall first be deducted from the current net revenue received by the city from such railroads and facilities and properties used in connection therewith and rights therein and securities owned by the city: (a) an amount equal to the interest and amortization requirements on indebtedness for rapid transit purposes heretofore excluded by order of the appellate division, which exclusion shall not be terminated by or under any provision of this section; (b) an amount equal to the interest on indebtedness contracted pursuant to this section and of the annual requirements for amortization on any sinking fund bonds and for redemption of any serial bonds evidencing such indebtedness; (c) an amount equal to the sum of all taxes and bridge tolls accruing to the city in the fiscal year of the city preceding the acquisition of the railroads or facilities or properties or rights therein or securities acquired by the city hereunder, from such railroads, facilities and properties; and (d) the amount of net operating revenue derived by the city from the independent subway system during such fiscal year. The legislature shall prescribe the method by which and the terms and conditions under which the amount of any indebtedness to be excluded hereunder shall be determined, and no indebtedness shall be excluded except in accordance with the determination so prescribed. The legislature may confer appropriate jurisdiction on the appellate division of the supreme court in the first judicial department for the purpose of determining the amount of any debt to be so excluded.