A pie or pie chart is a type of graph used to compare statistics. This chart is called a pie because it has the shape of a circle whose small parts are like slices of pie. This chart shows the parts of a total percentage in an easy-to-understand way, and can be a great way to share complex data. You can create a pie chart using a math compass, pencil, and some markers or colored pencils. You can also create pie charts using word processing software or free programs on the internet.
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Method 1 of 3: Creating a Digital Pie Chart
Step 1. Create a pie chart in Excel using graphic tools
In an Excel spreadsheet, type each data label in the column on the left. Type each relevant data point in the row next to it. Highlight labels and numbers by clicking and holding the mouse, then dragging across all labels and data points. Release the mouse and click the small icon that appears next to the number. Click “Charts” (diagram), then click “Pie Chart” (pie chart) to create a pie chart.
Notes:
The order of the list of data points determines the order in which they appear on the chart. This is important if you want to create sequential diagrams.
Step 2. Click the chart button in Word to create a pie chart
In Microsoft Word, click the “Insert” label at the top of the program. Click the 3 bars with the word “Chart” at the top of the page. On the left side of the window, click “Pie” and select the desired style. A new window containing a sample set of rows, colors, and titles will appear.
- Adjust the wording of each label to fully reflect the data it represents. Click and change the chart title so that it reflects the subject of the pie chart. Replace each number next to the label so that it represents your data.
- Any pie chart created in Excel or Word can be copied and pasted into PowerPoint.
- A pie chart created in Word will look the same as a pie chart created in Excel.
Step 3. Use a free online program to create a pie chart if you don't have Word or Excel
There are several free online sites where you can enter data and create pie charts. Search internet search engines for free sites that allow you to customize your design and enter your own scores. You may need to create a free account on some sites to download the diagram directly, but you can also use a screenshot program to take a picture of the diagram.
- Two of the most popular charting tools on the internet are https://www.meta-chart.com/ and https://www.onlinecharttool.com. Both let you control various design elements and enter your own information.
- To use the Meta-Chart, click “Pie Chart” on the main screen. Click the “Data” label to enter numbers and the “Labels” label to enter a name for each data point. Click “Display” to bring up your chart.
- To use the Online Chart Tool, select “Pie” from the drop down menu at the top of the screen. Choose the appearance, color and design. Press “next” to enter labels and data points. Click “next” and select a font. Click “next” again to create a diagram.
Method 2 of 3: Calculating Statistics
Step 1. Write down each data point and order it from high to low
Start with the highest number in the data set. Write on the top row a blank sheet of paper. Just below it, write the second highest number. Each number must be in its own row so that it forms a column of data points.
For example, if you are making a pie chart of the number of animals on the farm, list 24 cows in the top row, followed by 20 goats, then 6 chickens
Notes:
Whole numbers are easier to calculate so eliminate decimals as much as possible. For example, round 20, 4 to 20, or 5, 8 to 6. Your work will be easier and data will be less affected.
Step 2. Label each number you write down so you don't forget it
You can draw symbols or write labels based on the type of data the pie chart conveys. Write each label right next to it and inline with its corresponding number. This will make it easier for you to find out what each number represents.
For example, write “cow” next to 24, “goat” next to 20, and “chicken” next to 6. You can also use small pictures to represent each animal or shorten them to “S”, “K”, and “A"
Step 3. Add up all the numbers to get the denominator
Draw a horizontal line under the bottom number in the data point column, and add up all the numbers above it using a calculator. Write the result of adding the data under the horizontal line to get the denominator. You will divide the data points by this number to produce a decimal number.
- The denominator is the mathematical term for the number that is below the dividing line.
- Here, your goal is to divide each number in the data by the denominator to get a decimal number. The decimal number will reflect the percentage of the number of each data point. You'll need to multiply each decimal by 360 to figure out how big the share of the corresponding data points is in the pie chart.
- For the farm animal pie chart, add 24, 20, and 6 to get a total of 50. This is your denominator.
Step 4. Divide each number by the denominator to get a decimal number
Use a calculator to divide each data point by the denominator. Write this new decimal number next to the corresponding data point. Each decimal number must be less than 1, and the numbers in the new column must be sequential with the highest number at the top and the lowest number at the bottom.
- If there is a number that is more than 1, it means that something is wrong. Each number must be a decimal.
- For the farm animal pie chart, 24/50 = 0.48 cows, 20/50 = 0.4 goats, and 6/50 = 0.12 chickens.
Tip:
These decimal numbers work like percentages. For example, 0.44 is equal to 44%. This can help you determine the size of the pie slice for each data point. If the pie chart doesn't have to be accurate, you can stop here and use these percentages to make a rough sketch of the pie chart.
Step 5. Multiply each decimal by 360 to get the angle of each pie slice
Use a calculator to multiply each decimal by 360. Write each result next to a decimal number so that each set of numbers stays on the same line as the original data.
- It's a good idea to round the number to an integer. For example, you need to round 56.6 to 57. Unless you're creating a specific pie chart that requires minor calculations, stick to whole numbers to make the chart easier to read.
- For a farm animal pie chart, 0.48 cows x 360 = 172, 8, 0, 4 goats x 360 = 144, and 0, 12 chickens x 360 = 43, 2. Round 172, 8 to 173, then round 43, 2 to be 43.
Step 6. Add up all the numbers to check the work
Check your work again by adding up the previous calculations. If the total is 360, it's likely that your work is accurate. If the sum is 361 or 359, you've rounded the number in the wrong direction. If the numbers are far off the mark, it looks like you've missed something and should double-check your work for mistakes in your work.
In this example, 173 + 144 + 43 = 360 so you know that the corners of each pie slice will form the full circle of the diagram
Method 3 of 3: Draw a Diagram
Step 1. Use the math term to draw a perfect circle
To be fully accurate, prepare a compass and attach a pencil to one end. Press the needle on the other end of the compass at the point where the center of the circle will be. Rotate the compass by resting on the tip of the needle so that the pencil on the compass draws a perfect circle.
- If you don't have a compass and the circle doesn't have to be perfect, feel free to use any round object, such as the lid of a can, glass, or bottle, and trace it with a pencil.
- You can also use a pen, but all the mistakes made cannot be erased.
Tip:
You are free to determine the size of the circle! You only need to know the angles of each pie slice to create a chart, and it doesn't depend on the size of the circle.
Step 2. Draw a straight line from the center point to the sides of the circle to create a radius
Keep the compass in place and rotate the pencil so that it is at the top of the circle. Pull the pencil straight down towards the needle after loosening the hinges to draw the radius. Depending on the type of compass, you may need to set aside the compass, put a point at the center of the circle, and then draw a radius line from the center to the sides of the circle with the help of a ruler.
The straight line may be vertical (12 or 6 o'clock direction) or horizontal (9 or 3 o'clock direction). The next segment to be created can be clockwise, or counterclockwise
Step 3. Align the arc with the radius
Place a small hole in the bottom of the arc directly at the point where the compass needle was pierced. Align the straight line with the 90 degree mark on the arc.
The hole at the bottom of the arc is called the crosshair and is used to create a perfect 90 degree angle by making a straight line to the 90 degree mark on the arc
Step 4. Create each pie slice by moving the center point of the arc each time you add a line
Keep the center of the arc in the center of the circle and add up your first data point by 90. Find this number on the outside of the arc and make a mark. Then, draw a straight line from the mark to the center of the circle. Create a new line centered on the center of the arc for each piece of pie you are calculating
- For example, if you're making a pie chart of farm animals, the first number is 144. Add 144 by 90 to get 234. Make a mark at an angle of 234 degrees, and then draw your line. Rotate the arc and use the line you just created as a new 90 degree mark. The next data point is 43 degrees. Use the line you just created and add 43 by 90 to get 133 degrees. Make a mark at an angle of 133 degrees and draw a line to the center of the circle. The remaining pieces should have an angle of 17 degrees.
- You can use an arc base and skip the addition step by 90 degrees, if you like. However, you will be forced to draw it at an angle and mistakes are easy to make this way.
Step 5. Color each piece according to the specified key
Assign a differentiating key to each piece of the pie chart. Give each slice a different color so you can easily determine what each pie slice represents.
- Thicken the circles and pencil lines with a permanent black marker if you want the colors to stand out more.
- You can even use patterns to distinguish the pie slices in the diagram, such as cowhide patches, to represent cows!
