For purposes of determining the Federal medical assistance percentage applicable to an Indian tribe, a tribal organization, or a tribal consortium under paragraphs (1), (2), and (5) of section
674
(a) of this title, the calculation of the per capita income of the Indian tribe, tribal organization, or tribal consortium shall be based upon the service population of the Indian tribe, tribal organization, or tribal consortium, except that in no case shall an Indian tribe, a tribal organization, or a tribal consortium receive less than the Federal medical assistance percentage for any State in which the tribe, organization, or consortium is located.