The size of the bubble reflects the ranking position of the school.
We display up to 10 colored bubbles for each of our three main categories (red, blue and white). Sometimes the same school scores in more than one of the three categories. These schools will have overlapping bubbles, and on mouse over the ranking will be shown for each of the categories in which the school is ranked top 10.
Relative numbers means exercises solved relative to the number of students in the school (average solved per student).