2.4.26 The payment mechanism can include arrangements for indexing the unitary charge agreed at contract signature, i.e. varying the unitary charge according to a price or cost index, e.g. the Consumer Price Index. Indexation is typically used to vary the price according to inflation. This means that the public sector bears the inflation risk for the project since inflation risk is typically outside the control of the provider and is difficult to forecast accurately.
2.4.27 Generally, the indexation will only apply to a part of the unitary payment, instead of being applied to the whole unitary charge.