The purpose of this paper is to develop a methodology which can be used to set X-factor under price cap schemes, when the number of observations is limited. We firstly apply a panel index approach across Water and Sewerage companies (WaSCs) over time to decompose unit-specific index number based...

The purpose of this paper is the evaluation of various profit drivers such as price changes, productivity changes and quality levels on the financial performance of the Water and Sewerage Companies (WaSCs) over time in the case when the number of observations is limited. We thereby follow...