Abstract
Since privatized from Japan Highway Public Corporation in 2005, three Nippon Expressway Companies (NEXCOs) have surveyed the customer satisfaction for more than ten years. The score of satisfaction is one of the key performance indicators which explain the difference between customers' expectation and experience. This paper shows the change of satisfaction during the decade and possible factors affecting the result of survey. We confirmed that network extensions and facility improvements increased the satisfaction scores. Aging respondents also helped to increase the score. On the other hand, the negative effects were from an earthquake and a major accident. There is a combination of positive and negative effects that changes the satisfaction scores over the years.