34 C.F.R. § 300.700
(b) Maximum amount. The maximum amount of the grant a State may receive under section 611 of the Act is—
(1) For fiscal years 2005 and 2006—
(i) The number of children with disabilities in the State who are receiving special education and related services—
(2) For fiscal year 2007 and subsequent fiscal years—
(i) The number of children with disabilities in the 2004-2005 school year in the State who received special education and related services—
(iii) Adjusted by the rate of annual change in the sum of—
(B) Fifteen (15) percent of the State's population of children described in paragraph (b)(2)(iii)(A) of this section who are living in poverty.
(Authority: 20 U.S.C. 1411(a) and (d))