What is a Pie Chart?
A pie chart is a circular statistical graphic, divided into slices to illustrate numerical proportion. Each slice represents a category's share of the total, with the entire circle (or "pie") representing 100% of the data. The size of each slice is proportional to the quantity it represents.
How Pie Charts Work
The core principle is that the sum of all slices must equal a complete circle (360 degrees) or 100% of the data set. Data is converted into angles or percentages, where a larger angle or percentage signifies a larger proportion of the whole. They are best used for comparing a few categories at a glance.
A Practical Example
Imagine a survey asking students about their favorite fruits: 40% like apples, 30% prefer bananas, 20% favor oranges, and 10% choose grapes. A pie chart for this data would have four slices, with the apple slice being the largest and the grape slice the smallest, visually demonstrating each fruit's popularity relative to the total.
Importance or Applications
Pie charts are important for quickly understanding the distribution of a categorical variable within a whole. They are often used in business reports, educational presentations, and public statistics to show market share, budget allocation, or demographic breakdowns in an easily digestible visual format.