# Pie Chart Definition

Pie charts, which typically divide a circle area into parts to represent many categories, are used frequently for the visual representation of data. They are especially helpful when attempting to illustrate how various elements of a whole relate to one another. Pie charts are mostly used in Excel documents to represent data graphically.

## Defining Pie Chart

In order to display numerical data, a pie chart is represented as a circular graph that has been segmented into sectors or slices. The pie's entire surface reflects 100% of the data, with each slice proportionating to the amount of different data it represents.

Pie charts are often used to show how different parts of a whole relate to each other. For example, a pie chart might be used to show how a company's revenue is divided among different product lines. Pie charts can also be used to compare different sets of data. For example, a pie chart might be used to show how different age groups in a population are distributed.

Pie charts are easy to understand and interpret and can provide a visual representation of complex data in a simple way.

## Origin of Pie Chart

William Playfair, a Scottish engineer, is credited with inventing the pie chart in 1801. He used it to show how the British Empire's trade was divided among different countries. However, it is important to note that Playfair's invention was not the first use of this type of chart. Similar charts had been used by other mathematicians and scientists, such as William Jones in 1715 and Joseph Priestley in 1765.

Nevertheless, Playfair's use of the pie chart helped popularize it and became a standard data visualization tool in the following years.

## Characteristics of a Pie Chart

The following are the notable characteristics of a Pie Chart:

• Circular in Shape:A pie chart is circular in shape and is divided into slices, each of which represents a portion of the entire. Slices are grouped to depict the relative sizes of the various measurement categories as a whole.
• Proportional Representation: Pie charts are used in proportional representation to indicate how big various categories are in comparison to each other. The size of each slice is proportionate to the amount it reflects, with each slice representing a different percentage of the total.
• Simple to Comprehend:One of the main benefits of a pie chart is that it is simple to comprehend. Even for individuals who are not familiar with the charts, it provides a visual representation of the data that is simple to read and interpret.
• The Limited Number of Categories: Pie charts work best when there are only a few categories in the data to be displayed. If there are fewer categories, the pie chart might become less congested and more straightforward to read.
• No Negative Numbers: Pie charts are unable to show negative numbers. This is due to the fact that a pie chart cannot depict negative values as a percentage of the total or when there are angles and their proportions involved.

## Types of Pie Charts

Pie charts are one of the most common visual representation tools used to display data in a way that is easy to understand. They are an excellent way to communicate data in a simple and concise manner, making them ideal for use in a wide range of applications. Fortunately, there are many types of pie charts, such as:

### Basic Pie Chart

The basic pie chart is a circular graph arranged into slices or parts, each representing a different category or value. The size of each slice is proportional to the value it represents, with larger slices indicating a higher value. Basic pie charts are useful for displaying data with a small number of categories.

### Exploded Pie Chart

One or more slices of the pie are separated from the remaining portions in the exploding pie chart, which is a variation of the classic pie chart. The divided slice or slices become more visually prominent as a result, standing out more sharply. Exploded pie charts are helpful for highlighting specific regions or numbers.

### Doughnut Pie Chart

The standard doughnut pie chart typically consists of a hole in the middle. This results in a data visualization that is more condensed while maintaining the same degree of detail as a simple pie chart. When you wish to present data with a limited number of categories in a condensed and readable way, doughnut pie charts are helpful.

### Multiple Pie Chart

A variant of the basic pie chart in which numerous charts are shown side by side is known as a multiple pie chart. This makes it simple to compare data between several categories or values. When you need to display a lot of categories in a readable and understandable fashion, multiple pie charts might be helpful.

### Stacked Pie Chart

In the stacked pie chart, which is a variant of the basic pie chart, each slice is divided into smaller slices to represent various values falling under that category. This produces a visual depiction of the various values that make up each category. When you wish to display data with different values inside each category, stacked pie charts are helpful.

### 3D Pie Chart

The 3D pie chart is a variation of the traditional pie chart that shows the chart in three dimensions. This makes the material more aesthetically appealing but can occasionally make it more challenging to read and comprehend. When you want to present the data in a way that is more visually appealing, 3D pie charts might be helpful.

## Uses of Pie Charts

Pie charts have been known to be a very flexible tool for data visualization. They can be applied in a variety of fields, including science and research, as well as business and finance. Here are some of the most common uses of pie charts:

### Sales Data

Pie charts are a common way to show sales statistics. They can be used to display the percentage of sales in every class of product or in various markets or geographic areas. This makes it simple to identify the main sources of sales and potential improvement areas.

### Demographic Data

Pie charts can be used to show demographic information, such as the age, gender, or level of education of a specific group. This makes it simple to comprehend a population's demographics and may be helpful for marketing or advertising initiatives that are specifically targeted.

### Financial Data

Pie charts can be used to show financial information, such as the breakdown of budgeted expenses or the proportion of revenue derived from various sources. As a result, it is simple to see where money is being spent and where adjustments to generate more revenue can be made.

### Scientific Data

Pie charts can be used to show scientific facts, such as the distribution of a specific species or the composition of a specific material. Due to its simplicity, complex data sets can now be easily visualized, which is helpful for research and scientific publications.

### Marketing Data

Pie charts can be used to show marketing information, such as the breakdown of website traffic by source or the proportion of buyers that favor a specific product. This makes it simple to comprehend the efficacy of various marketing techniques and can be helpful when deciding on future marketing initiatives.

### Survey Data

Data from surveys, such as the proportion of respondents who provided a certain response to a question in a particular fashion, can be displayed using pie charts. This makes it simple to comprehend the survey data's broad trends and may be helpful when making decisions based on the findings.

### Project Management Data

Pie charts can be used to illustrate information about project management, such as the division of work into categories or the proportion of tasks that have been completed at each stage of a project. This facilitates project progress understanding and may be helpful in deciding how to allocate resources and set timetables.

## Attributes and Effectiveness of a Pie Chart

• Simple Design: Pie charts are simple in design, consisting of a circle divided into sections or slices, with each slice representing a portion of the whole. This simplicity makes it easy for viewers to understand and interpret the data.
• Easy to Understand: Pie charts are easy to understand, even for those who are not familiar with data visualization techniques. The circular design is easy to comprehend, and the slices clearly show the percentage of each category.
• Show Proportions: Pie charts are effective at showing the proportion of each category in relation to the whole. This attribute makes it easy to see which categories are larger or smaller and can highlight any significant differences between them.
• Visual Appeal: Pie charts are visually appealing due to their circular shape and use of colors. The use of different colors for each slice can make it easier to distinguish between categories and add an element of interest to the chart.
• Flexibility: Pie charts can be flexible in their design, as they can be adapted to show data in different ways. For example, a pie chart can be converted to a donut chart by removing the center of the circle, which can create a different but appealing visual effect.

## Limitation of a Pie Chart

• Difficulty in Comparing Values: Pie charts are not an ideal visualization tool when it comes to comparing values. It isn't easy to compare the size of one slice to another slice, as the human eye is not very good at estimating angles.
• Complexity: Pie charts are more difficult to grasp than other types of visualization because of their complexity. This is particularly true for pie charts with a large number of segments or categories. For instance, it can be challenging to read and comprehend a pie chart with more than ten segments.
• Inability to Show Trends: Pie charts should be more effective in displaying trends over time. However, the Pie charts cannot depict how data changes over time since they only display a snapshot of the data at one particular time. A superior visualization technique for displaying patterns over time is a line chart.
• Poor Display of Small Values: Pie charts are not suitable for displaying small values. This is because small slices are difficult to see and interpret accurately. In addition, small slices can be difficult to label, which makes it challenging to provide context for the data.
• Inability to Show Magnitude: Pie charts are ineffective at displaying magnitude. For instance, because the chart must convey an existence of scale, it can be challenging to determine if a slice reflects a relatively small or huge amount of data. When analyzing data sets or making conclusions based on the data, this could be an issue.
• Difficulty in Representing Negative Data: Pie charts are not effective at displaying negative data. This is so that a pie chart can't display negative values. Pie charts can make it difficult to comprehend the correlation between positive and negative numbers, which further complicates the analysis of the data.

## Differences between a Pie Chart and a Bar Graph

Two of the most popular ways to present data visually include using pie charts and bar graphs. They are suitable for many types of data and various methods of analysis despite having many commonalities and important distinctions. Considering various factors into account, let us discuss some of the notable differences between these two chart types:

• Data Representation: Pie charts represent data as a proportion of the whole, while bar graphs represent data as individual values. In a bar graph, each bar represents a discrete value, while in a pie chart, each slice represents a proportion of the total.
• Comparison: A pie chart is best suited for comparing the relative sizes of different categories, while a bar graph is best suited for comparing the individual values of different categories. If you need to compare the values of different categories, a bar graph is a better choice.
• The Number of Categories: A pie chart is best suited for displaying a limited number of categories, while a bar graph can display a large number of categories. A bar graph is a better choice if you have too many categories to display as compared to the pie chart.
• While a pie chart cannot display negative values, a bar graph can. Negative values are represented by bars that extend below the zero line.
• Continuous Data: Bar graphs are best suited for displaying continuous data, while pie charts are best suited for displaying categorical data at a certain time. A bar graph is a better choice if you have continuous data, such as temperature readings. If you have categorical data, such as types of fruit, a pie chart can be a better choice.
• Shape: The most obvious difference between a pie chart and a bar graph is their shape or design structure. While a pie chart is circular in shape, a bar graph is rectangular in shape.

## Conclusion

In conclusion, pie charts are a simple and effective way to present visually appealing data. Their attributes, including their simplicity, easy-to-understand design, and ability to show proportions, make them an effective tool for data visualization. Their effectiveness in presenting data clearly, comparing different categories, showing trends, focusing on important categories, and their visually appealing structure make them a valuable tool for presenting data in a clear and engaging way.