Subjective duration of every three-year period for 3 to 18 years of age, estimated by students.

Results indicated that both subjective time durations, one day and three years, are well described by the normal distribution if the time scale is logarithmic rather than linear. A remarkable finding obtained here is that in reference to the mean subjective time duration of the junior high school (three years), the mean subjective time durations for each of the three-year periods before elementary school were significantly longer than unity (about 1.2), and the subjective duration of the three year period of the senior high school is significantly shorter (about 0.8). When subjects transferred to other elementary schools at 6 to 11 years of age, the mean subjective time duration of the periods below 11 years of age was much longer, more than 1.3.