34 C.F.R. § 300.202
(a) General. Amounts provided to the LEA under Part B of the Act—
(b) Excess cost requirement—(1) General.
(2)
(3) If two or more LEAs jointly establish eligibility in accordance with § 300.223, the minimum average amount is the average of the combined minimum average amounts determined in accordance with the definition of excess costs in § 300.16 in those agencies for elementary or secondary school students, as the case may be.
(Approved by the Office of Management and Budget under control number 1820-0600)
(Authority: 20 U.S.C. 1413(a)(2)(A))