The FFPP (Price Adjustment Formula) is a mechanism for price updating to maintain the economic balance of a construction contract, which constitutes a price adjustment system in construction in Peru under the provisions of Article 2 of Decree Law 21825, published on March 30, 1977, subsequently developed by Article 5.6.1 of the Single Regulation for Bidding and Contracting of Public Works (RULCOP), subsection j of Article 26 of the Legislative Decree approving the State Contracting Law, and Article 49 of its regulation.

Concession Contracts for Infrastructure and Public Services (contained in Supreme Decree No. 059-96-PCM) provide for the existence of adjustment formulas for supervening causes, and when it is convenient to modify the concession, the parties will seek to respect, as far as possible, the financial balance for both parties. It should be noted that the concession contract cannot be modified by laws or provisions of any kind, in accordance with Article 62 of the Political Constitution. It can only be altered by agreement between the parties or through arbitration.

The application of FFPP aims exclusively at the preservation of the contract, its continuity in the execution of works, and the satisfaction of the public interests involved in the contract.

In Peru, the use of Polynomial Formulas and their regulation by D.S. No. 011-79-VC is currently regulated by the Regulations of the State Contracting Law approved by Supreme Decree No. 344-2018-EF, which does not apply to Concession Contracts.