What grade did you learn department statistics?

Mathematics fan chart of sixth grade in primary school.

Sector statistics chart uses the whole circle to represent the total (unit "1"), and the size of each sector through the center point o of the circle indicates the percentage of each part in the total. The sum of the percentages of all parts in the fan statistics chart is "1". But pie charts are not pie charts.

Through the fan-shaped statistical chart, the relationship between the number of each part and the total can be clearly expressed. Different from the broken-line statistical chart, it cannot reflect the quantitative change trend; Unlike bar charts, it is not easy to see various quantities.