The duration of the contract
1. In the notice launching the procedure, the period of the contract shall be set by the contracting authority in such a way that does not bind him for an indefinite or definite but disproportionate period of time, which would not be in compliance with the aim of maintaining competition and effective use of public funds, unless such a period of the contract is justified by the subject-matter, the chosen structuring of the contract, the terms of payment related thereto or the investment realized by the successful tenderer.
2. Works or service concessions may only be concluded for a limited period of time. If the duration of the works or service concessions exceed a period of five years, the contracting authority shall prove by calculation that the duration of the contract does not exceed the period in which the investments made by the concessionaire, over the duration of the contract, for the execution of the works or services or in relation to the performance of the contract may be, under reasonable assumptions, recouped and a reasonable return may be achieved on the capital invested.