assistance for families as the result of insufficient funding, as determined by the Secretary, and to avoid or reduce the proration of renewal funding allocations: Provided further , That the Secretary may make temporary adjustments to the allocations for public housing agencies in an area for which the President declared a disaster under title IV of the Robert T. Stafford Disaster Relief and Emergency Assistance Act ( 42 U.S.C. 5170 et seq.), to avoid significant funding reductions that would otherwise result from the disaster, upon request by a public housing agency and supported by documentation as required by the Secretary that demonstrates that the need for the adjustment is due to the disaster: Provided further , That up to $100,000,000 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