70 percent shall be allocated to such local educational agencies in proportion to the number of individuals aged 15 through 19, inclusive, who reside in the school district served by such local educational agency from families with incomes below the poverty line (as defined by the Office of Management and Budget and revised annually in accordance with section
9902
(2) of title
42) applicable to a family of the size involved for the fiscal year for which the determination is made compared to the number of such individuals who reside in the school districts served by all the local educational agencies in the State for such preceding fiscal year.