What is a pie chart?
The pie chart is probably one of the charts I’ve used most in my accounting career spanning 25 years. A pie chart is simply a circular chart separated into segments, with each segment representing a proportion. The arc length of the segment will be directly proportional to the quantity it is charting, with the total quantity equating to a full circle.
Pie charts are often used to produce a graphical representation of data that is easy to understand by non-statisticians. For example one use of the graph chart is portraying the results of an election – with a clear chart it is easy to tell which party or politician has won the election.
Many statisticians regard the pie chart as an inaccurate method of displaying graphical information as it is often difficult to compare the comparative sizes of each slice of pie especially when there are a large number of slices; however research has shown that generally people are able to make very good estimates based on the pie chart.
How to make a pie chart on Excel.
Pie charts are a fairly unique type of chart as they are more graphical in nature and present an overall view rather than detailed analysis. When creating a pie chart on Excel you will have to work out how you want the data presented and plan the data collection accordingly. The procedure below is the general procedure I tend to follow:
- Collate and set up pie chart data
- Create the pie chart using Microsoft Excel
- Format the default pie chart
- Consider using advanced pie charts
I will cover each of these topics in more detail below.
Setting up the pie chart data
I have decided to track a fictional pre-election campaign and the popularity of each candidate. I will use this data to help my own candidate decide if he needs to work harder to gain support. Now that I have the data I can begin to create my Excel pie chart.
The first thing I must do after collating the data is to transfer it into a spreadsheet (I am using Microsoft Excel 2010):
- Open a new worksheet in Microsoft Excel
- Add the headings Candidate, Popularity (%) and list the candidates in the Candidate column.
- I used the % format for the column Popularity as this is what I want to see in the pie chart. To do this select the are by clicking the top cell and dragging the outline to the end of the data. Right click on this range and use the format cells option. Click on the number tab and select Percentage in the category - for this chart I select 0 decimal places.
- Enter data for the % popularity for each candidate.
- I’m not interested in formatting the table of data as it will not be used in any presentation.
Creating a Pie Chart
Now that I have setup the data table within Microsoft Excel I can begin to create the pie chart; creating a chart in Excel is very easy but does rely on having the data setup before hand:
- Highlight the data table by clicking on the top left cell, click and hold the left mouse button and drag the box to the last cell in the data table. Make sure that you include the headings in the range.
- Using the Excel Ribon – click on Insert
- There are now some additional menu items available. Click on the small arrow under Pie. You are given a small graphical representation of different Pie Charts - I selected Pie as I'm only interested in one data series and want a simple pie chart.
- Microsoft Excel will automatically create a pie chart based on your data.
How to change the pie chart format
Excel will create a default Pie Chart from your data. Excel automatically uses your data to add labels and create the relevant axis. However I’d want to amend the chart and change the colors and formatting:
Looking at the pie chart on the spreadsheet you may see a border surrounding the chart with dots at the edges and corners - these dots give you various options – holding down the left mouse button you can grab the dots and then can alter the shape and size of the chart. (If the border is not there yo can click anywhere on the chart). When you select the chart by clicking on it new menu items appear in the Microsoft Excel Ribbon:
- Design – gives you options for changing the style or design of the chart. If you want you can even amend the type of graph.
- Layout – allows you to change the detailed information of the chart (Headings, labels etc.) - there is quite a lot you can do in the Layout menu ranging from creating second axis to adding trend lines.
- Format – allows to for formatting of items such as font of text, size of text etc. This is where you turn a default pie chart into something that looks very clear and professional.
First change the design of the chart.
- In the Chart Layouts section in the Design menu I chose Layout 6.
- In the Chart Styles section in Design menu I chose style 31.
Next change the Layout of the chart.
There are a lot of things that can be changed in this menu; Microsoft gives you a lot of options for changing the layout of the chart - the best way is to try to use some of the functionality to see what they do. For the purposes of this article I’ve decided to add move the %s to a better position.
- In the Labels section in the Layout menu I clicked the down arrow under Data Labels and clicked on Outside End
To finish, change the format of the chart.
This is where you can give your chart a professional look:
- Using the shape styles of the format sub-menu I chose the Aqua Accent 5 - this added a blue shaded background color to the chart. Advanced users can use Shape Fill and other tools to change the style of the chart.
- Using the WordArt section of the format sub-menu I used Aqua 4pt glow within the Text Effects and added a mirrored effect to make the text stand out.
Amending the text within the pie chart.
When you changed the type of pie chart you are using some of the headings may change or disappear. Simply click the relevant text and amend the heading. You can also add additional text and headings in the Layout menu - labels section.
Final thoughts about creating pie charts in Microsoft Excel
Microsoft Excel is a very powerful tool that allows you to create and amend charts and graphs. The functionality of Excel allows you to create very professional looking pie charts that not only graphically represent your data well, but also can be added to presentations and other Microsoft Office applications.
For the final pie chart I decided that I wanted to highlight my candidates percentage and created an exploding pir chart - this was done simply by grabbing the relevant pie segment and dragging it to the position I wanted it.