Methods for determining worst-served customers

The paper outlines the service quality measurements in general and analyzes them from the customer´s point of view. Applied procedures of worst-served customers including so-called guaranteed standards are introduced. From the overview the paper finds out that there are several but different methods for determining worst-served customers. The paper concludes that the definitions do not cover important fields from the customer´s point of view e.g. voltage quality. The paper proposes to set stricter targets than Guaranteed standards for worst-served customers and gives comments on guaranteed standards if they are used for worst-served customers.