It's a common misconception that all percentages warrant the use of a pie chart. Amy Balliett explains why this isn't the case, what you should use instead when a pie chart isn't right, and what the proper usage of pie charts really is.
[Instructor] Pie charts depict a portion of a whole. Now that might seem like trivial information, but you'd be amazed to know just how often this simple fact is misunderstood. You see, more often than not, people see a percentage as a data point and default to displaying that percentage in a pie chart. And 90% of the time, a pie chart is the best way to visualize a percentage. But again, remember that a pie chart depicts a part of a whole.
So what happens when the percentage is not a portion of a whole but is instead meant to show an increase or a decrease over a specific number? Well, think back to that seventh data vis mistake from the previous movie. The number was showing a 28% year-over-year increase in sales. Visualizing this as a pie chart would not make sense. The sales were not 28% of a total number. Instead, they were 28% more than the number from the previous year.
So now you know when to use pie charts and when not to, right? Use pie charts when you are trying to show a portion or portions of a whole and use other means of visualizing the data when the percentage is meant to show growth or decline. But what about how to create pie charts? Well, let me show you some easy ways to use pie charts in Adobe Illustrator. Start by clicking and holding the chart tool.
Then choose the pie chart option that you see over here. You'll see your mouse turn into crosshairs. Now when you click and drag, you'll see the outline of a box. Now this box can be any size and what's important to note is if you let go at certain sizes, the pie chart won't actually be a perfect circle. So hold the shift down and you'll see it springs to a perfect square. And when you let go, you'll actually have a perfect circle. The next thing you'll see is an Excel spreadsheet-looking pop-up window.
This is where you input your data for any chart or graph that you create in Adobe Illustrator. Let's pretend I want to show a pie chart that depicts 30%. Maybe there's 30% of people who love pie charts. Well, if I type 30 in right here, you would think I'd be done. But when I hit the check mark, nothing happens. Remember the rule: a pie chart is a percent of a whole. So I need to show the whole. 30% means 30 out of 100.
So the difference of 30, or 100 minus 30, is 70. When I type in that 70 and hit enter, I get a perfect pie chart. Now you'll see that you could also type the numbers in from top to bottom. I've typed them in left to right and that's very intentional. If I were to hit this button that transposes the numbers and makes them go top to bottom, and then I hit check, a completely different visualization appears.
This visualization is using the size of the circles to depict an amount where this shows 30% and this shows 70%. The problem here though is that this doesn't actually properly visualize information. But that's for another video to talk about. In this, we're going to keep focusing on creating a good pie chart. So I'm going to go ahead and transpose those numbers again. Now because I'm showing 30%, I've chosen to put the number 30 first.
If I put the number 70 first, and then I put the number 30, you'll actually notice that the 30% pie chart moves to the left. Since people read left to right, they also read clockwise. It's very important to make sure that the number that you're trying to show is the first number that appears in your chart and therefore appears in your pie chart as well. Now let's pretend that you want to show multiple numbers. Maybe 30% of people love pie charts and 20% of people like pie charts and only 10% of people are okay with pie charts.
Now that I have the 30, 20, and 10 in here, I need to come up with the difference which is 40%. When I type in the 40% and I hit check, I have a perfect pie chart again showing 30, 20, 10. You'll also notice that I actually organized these from largest to smallest because it's much easier to take in the information that way. Now what happens if I don't put that 40 in. Well if I delete that 40 and I hit enter, and the check mark, what you'll see is a big mistake.
This is not 30%, it's 50%. This is why it's incredibly important to add all of your numbers up to 100. And finally, when I put that 40% back in and I hit check, like I said, I have a great pie chart here, but it's really important to make sure that the darker color is your fill color. So we would want this slice, this slice, and this slice to all be darker colors. Whereas this slice should be a lighter color.
In a future video, I'll show you how to take this pie chart, change the colors, and really dress it up. But for now, let's move on to the next video which is all about bar graphs.
To succeed in design and marketing today, one must know how to interpret and properly visualize data. This course, developed and led by Killer Infographics CEO, Amy Balliett, walks you through the ins and outs of creating accurate and compelling data visualizations. Amy focuses on best practices, not tools, although she does provide an overview of Illustrator graphing features. Using these tips, you'll learn how to stand out from the crowd and create charts and graphs that combine precision with visual appeal.
- What charts and graphs work best for different types of data
- Putting data into visual and textual context to ensure it is accurate
- Visualizing data that doesn't lend itself to imagery
- Adding visual appeal without sacrificing accuracy
- Using the Adobe Illustrator graphing tools
- Avoiding common data viz mistakes