According to the individual analysis of the attributes also revealing results were found. For example, almost
all the attributes show a growing tendency across the years, but with lower average values of the perceptions
scores in 2008 and 2012 (as happened with the stated overall evaluation and the calculated service quality index).
In general, passengers are more dissatisfied with Fare, Frequency and Timetable (with values under 6.5 in almost
all the years), and most satisfied with Courtesy and Safety (with values over 7). One of the most important
changes produced in the perceptions of the attributes was for Fare, which fell down more than one point in the
last year. Service suppliers should focused on discovering the reasons for which Cleanliness, Space,
Temperature, Punctuality, Frequency and Timetable were evaluated as poorer in the last year, in order to solve
the possible problems.