(D) The dollar amount calculated under subsection (a)(6)(C) shall then be divided by the total number of months that the passthrough may apply pursuant to subsection (a)(6)(E)(i), to determine the monthly per unit costs for that tax year of the repayment of general obligation bonds.
(E) Landlords may pass through to each unit in a particular property the dollar amount calculated under subsections (a)(6)(A)–(D), as provided in this subsection (a)(6)(E).
(i) All passthroughs shall apply for the same number of months covered by the property tax bills used in the passthrough calculation, and the calculation may not be based on tax bills issued more than three years prior to the year in which the passthrough was imposed.