By providing for the application of the quarterly commercial rent index referred to in the first paragraph of Article L. 112-2 of the Monetary and Financial Code “if it is applicable”, the Law of 4 August 2008 on the modernisation of the economy (LME) may legitimately raise the question of what latitude is left to the contracting parties in situations other than that of a sliding-scale clause.

Beyond this legal question, and assuming that the parties to the deed have a choice between the ICC (construction cost index) and the ILC (commercial rent index), it should be asked which index is, from an economic standpoint, the more advantageous for one or other of the parties to the contract.