funding, as determined by the Secretary, and to avoid or reduce the proration of renewal funding allocations: Provided further , That up to $75,000,000 shall be available only: (1) for adjustments in the allocations for public housing agencies, after application for an adjustment by a public housing agency that experienced a significant increase, as determined by the Secretary, in renewal costs of vouchers resulting from unforeseen circumstances or from portability under section 8(r) of the Act