; and (II) the amount that would be applied under such paragraph if 100 percent were substituted for 106 percent . (ii) In the case of a single source drug or biological, an amount equal to the difference between— (I) the amount that would otherwise be applied under paragraph (1)(B); and (II) the amount that would be applied under such paragraph if 100 percent were substituted for 106 percent . (iii) In the case of a biosimilar biological product, the amount otherwise determined under paragraph (8)(B). (iv) In the case of a drug or biological during the initial period described in subsection (c)(4)(A), an amount equal to the difference between— (I) the amount that would otherwise be applied under subsection (c)(4)(A)(ii); and (II) the amount that would be applied under such subsection if 100 percent were substituted, as applicable, for— (aa) 103 percent in subclause (I) of such subsection; or (bb) any percent in excess of 100 percent applied under subclause (II) of such subsection. (v) In the case of a drug or biological to which subsection (d)(3)(C) applies, an amount equal to the difference between— (I) the amount that would otherwise be applied under such subsection; and (II) the amount that would be applied under such subsection if 100 percent were substituted, as applicable, for— (aa) any percent in excess of 100 percent applied under clause (i) of such subsection; or (bb) 103 percent in clause (ii) of such subsection. (C) Maximum add-on payment amount specified For purposes of subparagraph (A), the maximum add-on payment amount specified in this subparagraph is— (i) for each of 2021 through 2028, $1,000; and (ii) for a subsequent year, the amount specified in this subparagraph for the preceding year increased by the percentage increase in the consumer price index for all urban consumers (all items