A cumulative distribution is a plot of the number of observations that fall in or below an interval. For example, they are often used to determine where scores fall in a standardized test. For example, the x-axis (see bar graph illustration) shows the intervals of scores (such as the interval labeled 35 shows any score from 32.5 to 37.5, and so on) and the y-axis shows the number of students scoring in or below each interval. This graphically illustrates for the students (and teachers) how well they did on the test compared to other students.