It also says its 35 million existing customers should not expect any decline in service quality.
America's budget airlines are starting to move upmarket in service quality, whereas Europe's give every impression of moving relentlessly downmarket.
In some cases, there may have been declines in service quality (the postal service comes to mind) that are not reflected in the index.
The consumer body estimates that prices could be cut by between 19% and 26% next year - depending on the individual company - without any deterioration in service quality or reduction in environmental improvement measures.
James Bradford Ramsey, general counsel for the National Association of Regulatory Utility Commissioners, said state regulators were not eager to regulate the industry but would act if the companies did not fulfill their promises of improvements in service quality.
They know that the true promise of customer data is to help them to discriminate, in service quality and perhaps in price, and to target their services so that they give priority to the most profitable folk on their books.
With dozens of hospitals already in financial deficit, and with the threat of industrial action, it is unlikely such strategies could be deployed again without either a damaging decline in service quality or in staff morale.
Fuzzy set theory has also been used in service quality research.
Previous research has shown that employee job satisfaction is a relevant factor in service quality improvement.
The study reviews and reflects on research arguments in service quality measurement of a tourist attraction.
With thousands of Internet service providers popping up all over the place, there are big differences in service quality.
