Assessing potential changes in retail costs 2015-2020 - Water UK

First Economics—––—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–—–———–—–—–—–—–—–Figure 5.3: Selected RPI componentsSource: ONS.The charts show that the selected SPPI indices grew by between 15% and 35% over a 12-year period. The selected RPI indices grew by between 65% and 80%.5.3 ConclusionsOnce again, the precise numbers here are not especially important. What matters is that allof the comparator industries have seen costs escalate over time by a non-trivial amount.This reinforces the expectation that there will naturally be an escalation in water retail costs.22