Last month’s challenge was a frequently used graph: the basic bar chart (nearly 90 people shared their bars!). This month, as promised in the latest podcast episode, I’m going to challenge you to take on something less common: the square area graph. This is also known as a waffle chart. I tend to dislike charts that can be described as food—pie, donut, spaghetti, lasagna—so I don’t usually call it that (I realize some people may take issue with this, but that’s not going to stop me). I’ve also heard it called a unit chart, though for me unit charts use an icon to represent values (as described here by the Information Lab), whereas the square area graph uses...well...squares.
Whatever you choose to call it, these types of visuals can be useful in a couple of situations. I’ll give you some insight into scenarios where I’ve used square area graphs and illustrate each through example. If you plan to participate, be sure to read the instructions at the end of the post, as there are some important steps to take if you’d like yours to be included in the recap (most important: email your entry to SWDchallenge@storytellingwithdata.com). Here are some thoughts and examples on how I’ve used square area graphs:
To compare numbers of vastly different magnitudes
I see a bad thing done sometimes to bars when trying to compare numbers of very different magnitudes: the broken y-axis. This is when someone cuts a chunk out of the middle of the y-axis (often, this is denoted by a zigzag or diagonal line or set of lines on the axis or bars). This invalidates the visual comparison (the same way starting a bar chart at something other than zero does—don’t do this! If you aren't convinced, read more). The square area graph can sometimes be an alternative here. With bars, you only either get height (in the case of a vertical bar) or width (in the case of horizontal bar), whereas with a square you get both height and width. This allows us to compare numbers of different magnitudes in a more condensed space. Here’s an example illustrating this from the SWD blog archives (view full post):
An alternative to the pie chart
The square area graph can also sometimes work as an alternative to the pie chart. It’s worth noting that because we’re looking at areas, this chart type does fall victim to some of the same challenges as the pie chart (namely, our eyes aren’t great at measuring areas, making specific comparisons difficult). You do get some benefit, though, because you have the x- and y-axes on left/right and top/bottom, which means you have a few consistent baselines for comparison. We tend to overestimate areas, so having the “waffling” or gridlines forming the squares becomes important. I should also note that, depending on what you’re looking at (and how you determine it best to aggregate the data if you do so) while your units will be squares, you may not end up with a perfect square as your overall shape, which is ok.
The following is an anonymized example from one of my client workshops:
When presenting live
While the presenting live scenario isn't fully sufficient reason to use a square area graph—the data must first lend itself well to this format—the live presentation does give you additional flexibility. Because square area graphs are less common, it can mean we face a hurdle getting our audience to understand what we’re showing. In a live setting, you can help this less-familiar graph feel more accessible by building it piece by piece while talking your audience through what you are showing. When I introduced the previous example to its intended audience, I built it piece by piece. Let’s check out another example where I show you the full progression. Again, this is a real example, where I've changed the details to preserve confidentiality (press the play button in the middle to see the progression; there's no audio in the following video, only images).
If you are looking at these examples thinking “that looks kind of cool, but can I do that in my tool?”—you are not alone. This question is posed to me nearly every time I discuss the square area graph. While it may look fancy, my method is quite ineloquent. I consider this “brute force Excel” at its best: in the examples above, I’m working directly in an Excel spreadsheet, where I’ve sized the cells to be squares and manually formatted them to get the resulting visuals. It isn’t fancy, but it works. That said, I’m pretty sure there are tools and add-ins that make this easier. I haven’t used any of them, so if you’re aware of these and would like to share so others can benefit, please leave a comment on this post with details.
All of that is prelude to the challenge I pose to you: find some data of interest and create a square area graph. Share it so we can all see and learn! DEADLINE: Tuesday, 4/10 by midnight PST. You must EMAIL YOUR ENTRY to SWDchallenge@storytellingwithdata.com for inclusion in the follow-up post. I know we missed a number of people with the last recap, but it’s because we can’t go searching for your graphs. Given the volume of entries we’re receiving (and how manual the process currently is), we are not able to scrape Twitter, LinkedIn, etc. for submissions. The way to ensure inclusion is to send them to us. Full submission instructions follow (please do follow them, it makes our lives much easier!).
- Make it. Identify your data and create your visual with the tool of your choice. If you need help finding data, check out this list of publicly available data sources. You're also welcome to use a real work example if you'd like, just please don't share anything confidential.
- Share it. Email your entry to SWDchallenge@storytellingwithdata.com by the deadline. Attach your image as a .PNG. Put any commentary you’d like included in my follow up post in the body of the email (e.g. what tool you used, any notes on your methods or thought process you’d like to share); if there’s a social media profile or blog/site you’d like mentioned, please embed the links directly in your commentary (e.g. Blog | Twitter). If you’re going to write more than a paragraph or so, I encourage you to post it externally and provide a link or summary for inclusion. Feel free to also share on social media at any point using #SWDchallenge.
- The fine print. I reserve the right to post and potentially reuse examples shared.
I look forward to seeing what you come up with! I love seeing the varied topics and learning new things through this challenge. Stay tuned for the recap post in the second half of April.
Check out the #SWDchallenge page for all of the monthly challenges and recaps!