If you’ve read this blog before, or heard me speak, then you know that designing data visualization makeovers is one of my favorite activities of all time.

I love redesigning pie charts, in particular.

The vast majority of data visualization trainings just advise people to stop using pie charts… without teaching people what to do instead.

Every year, I work with dozens of organizations, and every single organization still has pie charts sprinkled throughout their reports, slideshows, dashboards, and infographics.

Hearing that you’re supposed to avoid 3D exploding pie charts with a hundred tiny slices is beginner-level stuff. I need to train you on useful alternatives–that’s the advanced-level stuff.

I created this before/after pie chart makeover a million years ago but forced myself to wait until March 14 to share it. Phew! It’s been a long wait.

Before: Two Pie Charts

I recently worked with a grantmaking organization. They awarded grants to support various research projects. For anonymity, I’ve changed the names of the research projects to A, B, C, etc.

The grantmaking organization simply wanted to look for patterns in their funding over time.

Their “before” version looked like this:

Two Slices Only

A major guideline for pie charts is that they’re easiest to read with only two slices.

At the very least, we’d need to collapse the seven slices into just two slices. For example, you may choose to focus on research topic A with a dark-light contrast.

Dark-light contrast is helpful, but it’s not enough. We have to keep editing.

Don’t Make Viewers Zig-Zag Their Eyes Across Different Graphs

Another guideline—for all charts, not just pies—is that you don’t want to make viewers make comparisons across multiple charts.

If you want them to make comparisons, then put those things next to each other, not several inches apart from each other.

Here’s how my eyes have to zig-zag back and forth to read the original:

The collapsed, two-slice version still requires zig-zagging eye movements:

Let’s make the comparisons faster and easier.

The grantmaking team and I put our heads together. We came up with a few alternatives.

After: Stacked Columns

Being researchy types, the first alternative we came up with was stacked columns. Stacked columns are just rectangular versions of pie charts.

There’s nothing inherently wrong with stacked columns. But, yikes! This alternative felt way too busy. There are seven segments in each column, which is too many…

… unless…

…. you use dark-light contrast to focus your viewer’s attention one just one segment at a time.

After: Slope Graphs

Since we’re comparing patterns over time, how about a slope graph?

A slope graph is a fancy name for a line graph that has exactly two points in time.

Spaghetti Slope

Here’s what we tried:

Yikes! We had good intentions, but we accidentally created a spaghetti slope graph.

When this happens, don’t fret. It’s not your fault. It just means your particular dataset had percentages that criss-crossed and overlapped too much.

Spaghetti Slope with Highlighting

There are a couple ways to detangle spaghetti graphs.

One option is to guide viewers’ eyes to just one thing at a time with dark-light contrast:

Which line(s) will you highlight?

Use your best professional judgment.

Think about your unique audience. You might highlight something that increased, like B. Or you might highlight something that decreased, like D. Or, you might highlight something that remained steady over time—perhaps that thing was supposed to go up or down, but didn’t, and you’ve got an interesting story to discuss.

Small Multiples Slope

Another way to fix a spaghetti graph is with a small multiples layout.

Small multiples means multiple small charts.

You could produce seven mini charts, one for each of the seven research topics.

But better yet, let’s group them into categories that will give our viewers more insights into the patterns—the fact that some research topics received more funding while other topics received less funding.

I color-coded by category (one color for increases, another color for decreases).

Finally, I added icons to boost memorability.

This one’s my favorite. Swoon.

After: Dot Plot with Arrows

I intentionally sorted the categories into those that increased and those that decreased. It’s kind of like a small multiples dot plot.

I also included arrows, instead of just regular ol’ circles or dots, to reinforce the direction of the changes.

I color-coded by category (increases in one color, decreases in another color).

Finally, I added icons to boost memorability.

Join the Conversation

Team, you know the drill! Comment and let me know which alternative is your favorite and why. I’m personally drawn to the small multiples slope graph.

Bonus! Download the Materials

Purchase the spreadsheet that contains these graphs.

Purchase the Materials

The post Stop Making People Read Across Multiple Pie Charts (& Here’s What to Do Instead) appeared first on Depict Data Studio.

I recently partnered with a school system to visualize data about the percentage of their students who quality for free or reduced-price meals. In the United States, Free and Reduced Meals (a.k.a. FARMs) is basically how we measure poverty in schools. The more students who are eligible for free lunch (based on their family’s income), the more students who are low-income.

Before

Here’s the before version.

They wanted to compare one of the schools to the district as a whole.

The nested design almost made sense because it almost easily allows us to compare the school and district.

But the concentric circles throw off the proportions. Do you see the magenta segments? The outer ring is larger than the inner ring, so the outer five percent is incorrectly larger than the inner five percent. Oops!

After

Let’s look at three possible ways to better tell our story.

Stacked Columns

Here’s my first attempt. At the very least, we need to transform our circles into rectangles.

For all of these makeovers, I selected two colors: one color for the district and another color for the school. I also made the District and School text stand out in a large font size. You would use your own branded colors and fonts, not mine.

My Former Researcher Brain loves stacked charts. Researchy types like me tend to default to this layout. I’m not sure why… just because we’re used to stacked charts?

There’s nothing inherently wrong with stacked charts. They just tend to be overused. Even though I design data visualizations for a living, I still can’t shake my Former Researcher tendencies, and I tend to draft reports with way too many bar charts. As I’m editing my own work, I look for places where I can swap out my overused bar chart for another chart type. I don’t include variety just for variety’s sake. I look for places where the chart’s messaging might be clearer through another chart type.

Waffle Charts

Another option is a waffle chart, like these two waffles. Waffles contain 100 little squares. They’re like square pie charts.

This approach almost works. I like it, but I don’t love it. I’m not in love with the labels. I tried creating text boxes for each of the segments—e.g., 27% free meals or 5% reduced meals—but it was impossible to arrange the text boxes on top of the waffle without looking cluttered or busy. Then, I moved the text boxes to the top of the graph, where they are now… but the viewers have to zig-zag their eyes back and forth between the words and the squares. Good. But not great.

Icon Arrays

Or, go big-picture with icon arrays. I love this approach, and the school district did, too.

In this icon array, we intentionally collapsed the categories—we combined free and reduced into a single category—to focus on big patterns so that our audience wouldn’t get lost in the weeds.

We also intentionally transformed the percentages into whole numbers, which is a better approach for non-data people (i.e., regular people who don’t stare at spreadsheets all day). Whole numbers are a lower numeracy level than percentages, so more people will understand the information.

And we intentionally focused on small numbers—3 in 10 students instead of 30 in 100 students—so that the numbers feel more tangible.

Want to try icon arrays yourself? A heads up: You must be comfortable with rounding. Thirty-two percent of students in the district qualified for free or reduced meals, but I rounded that 32 down to 30. I don’t suggest coloring-in part of an icon. Partially-colored icons can get confusing, especially if you’re using those little people icons.

Icon arrays shine when you need an at-a-glance overview. For example, you might use icon arrays for slideshows or executive summaries. You can save the nuanced stacked columns or waffles for the body of the report.

Your Turn

This isn’t an exhaustive list of options.

What additional designs can you come up with?

Bonus: Download the Materials

Want to explore how I made these visuals? Download the slides and use them however you’d like.

Download the Slides

The post Students Receiving Free and Reduced Meals: From Nested Donuts to an Icon Array appeared first on Depict Data Studio.

Before

Here’s a screenshot from one group’s (public-facing) research report. The authors of the report talked about wheelchairs that were given to people in other countries. This was the demographic section of the report so there were a few graphs showing who those wheelchairs went to — men, women, kids, adults, and so on. There are 3D pie charts but I don’t fault anyone for their before graphs. We’ve all been there.

After

The first pie chart was about gender–the proportion of wheelchairs distributed to men and women. According to my seven pie chart guidelines, gender can stay in a pie chart. Gender is a nominal/categorical variable and there are only a couple slices. We just need to reformat things a bit to make the graph easier to read. The before version is 3D, so the chart’s height makes the slices look larger or smaller than they really are. 3D distorts data.

There’s a legend below the chart so viewers would have to zig-zag their eyes back and forth to figure out which color corresponds to which slice. And the viewers would literally be zig-zagging because men are on the left side of the pie and on the right side of the legend, a software oddity. The after version is 2D; has labels directly on top of the slices to avoid wasting time hunting for information in the legend; and it uses colors from the organization’s logo rather than the software program’s default color palette.

The second pie chart was about age ranges–the proportion of wheelchairs given out to younger people and older people. According to my seven pie chart guidelines, age ranges can’t stay in a pie chart because age range is an ordinal variable. There’s a natural order or progression from younger people over to older people, so we need the chart to reflect that built-in characteristic. You could display these age ranges in a stacked bar chart or in a histogram. I went with a histogram because the 0-5 years segment was tiny and nearly invisible in a stacked bar chart. It’s faster to read left to right (the histogram) than to start at 12 o’clock and read clockwise (the pie).

I never cease to be amazed how small edits lead to a big impact. This page of the report looks completely different!

No, I didn’t keep the tables. When we see tables and graphs beside each other, our brains wonder whether the table matches the graph. Is this the same thing? Or different? Wait, it’s the same, right? So why did they include both? Oh, for the raw numbers? The graph has the percentages but not the numbers? That’s the only added value of the table? Redundant tables and graphs are unnecessarily burdensome for viewers. My rule of thumb is to display raw numbers for anything below 100 (3 of 7 people, not 43%) and percentages for anything above 100. We’re talking about well over 100 units here (either 886 or 866 wheelchairs, what an unfortunate typo) so we could’ve just displayed percentages in the pie chart and left off the raw numbers altogether.

However, this report was written for a technical audience, and technical audiences love extra details like numbers and percentages, so I simply included both within the after version.

Sometimes workshop attendees are afraid that including graphs will lengthen their reports. On the contrary, data visualization often decreases your report’s length. I freed up space by deleting the redundant tables. I decided to use that space for titles and subtitles to explain each graph. Before, the graphs were just slapped into the report without any explanatory text. I’m a visual person and prefer to read graphs over paragraphs. Other people prefer to read the paragraphs over graphs. Both viewers’ preferences are met when we add explanatory text alongside graphs.

The post Pie Chart Makeover: Transforming a Research Report appeared first on Depict Data Studio.

Does your organization need to track how much money you’re making and spending?

I see way too many revenue and expenses numbers gathering dust in hard-to-read pie charts.

In this blog post, you’ll see how transforming your pie charts into a dashboard–built in good ol’ Microsoft Excel–can be more useful for your organization’s leaders.

Before: Comparing Across Pies

A couple weeks ago I was in Birmingham with the Alabama Power Company’s grantees. We spent two days learning data visualization principles and producing makeovers of their graphs.

One of the grantees was presenting their revenue and expenses data like this, in two pie charts.

I changed their numbers and categories in this anonymized version, but revenue included things like grants from foundations and expenses included things like payroll.

I’m not anti-pie but I do have a long list of pie chart guidelines.

These numbers can’t stay in a pie chart because:

• there are too many slices;
• we can only show one pie at a time—not two beside each other; and
• pie charts are only useful for showing a single snapshot in time (this group needed to compare quarterly spending, and pies can’t show trends over time).

After

Let’s look at three data visualization makeovers.

They get a little more helpful each time!

The Bare Minimum: Pies into Bars

At the very least, we need to convert the pies into bars. It’s easier for our brains to compare the lengths of bars than to compare the slices/angles/area of pies.

Yes, we could get fancy by making the expenses bars go towards the left since those are technically negative numbers.

Add Context to the Bars

I try to anticipate what types of mental math the viewers will be doing.

The organization’s leaders and Board members will probably need to know the total revenue and total expenses.

Rather than making those viewers do mental math or tally the numbers in the margins of their handout, I inserted text boxes with the totals.

What They Really Need: A One-Page Dashboard

The pie charts and bar charts above were only giving the viewers a single snapshot in time. To manage effectively, leaders need to monitor trends over time.

Imagine what this Board meeting would look like: the attendees have a handout about the fourth quarter’s revenue and expenses. Seeing the fourth quarter’s numbers is great, but what about the third quarter? Did we spend more, less, or about the same as the prior quarter?

The attendees would have to search through the stack of papers in their folders to find the prior quarter’s handout, place the two pages next to each other on the table, and then zig-zag their eyes back and forth across the table and try to make comparisons. Viewers should never have to lay two pages beside each other or scroll through documents to make comparisons. That’s your job as the designer: to anticipate what they need to compare — quarterly spending — and place those comparisons as close as physically possible.

I designed a one-page dashboard that did just that — placed the quarterly numbers directly beside each other to make comparisons natural and easy.

I visualized quarterly patterns with spark lines so that viewers could generally see whether numbers were going up, going down, or holding steady over the course of the year. Then, I anticipated that viewers would need to know the year-end totals for each of the categories. Viewers should never have to do mental math; you should do the math for them.

I visualized the year-end totals with data bars. Yes, we could’ve gotten fancy and made the expenses bars go towards the left to reflect that expenses are negative numbers.

And yes, we could’ve added a row at the bottom that calculated the difference between each quarter’s revenue and expenses to see whether we were cash-flow positive. This group’s priority was monitoring how things changed over time, so the design reflects that priority.

Quite an improvement over the pie charts, don’t you agree?

Bonus: Watch the Video Lesson

Want more behind-the-scenes details? Here’s a 13-min video for you.

Bonus: Download the Templates

Want to design your own revenue and expenses dashboard?

Purchase the templates, register for the Dashboard Design course, bring me in for a private workshop, or borrow my brain during a consulting session.

The post Monitor Your Organization’s Revenue and Expenses with a Dashboard in Microsoft Excel appeared first on Depict Data Studio.

Let’s walk through a real-life example!

A few weeks ago I was in Indianapolis with the juvenile detention alternatives initiative. This group wanted to graph:

• how many youth went to juvenile detention centers,
• by gender, and
• by quarter.

Brainstorming

There are a dozen ways to graph each dataset. For this data, we could utilize:

1. table
2. heat table
3. quarter-by-quarter pies (well, not the best choice)
4. one year-end pie
5. line graph with numbers
6. small multiples line graphs with numbers
7. clustered bar
8. small multiples bar
9. stacked bars with numbers
10. stacked bars with percentages
11. stacked area with numbers
12. stacked area with percents
13. and probably a few more that I haven’t thought of yet

Before: Quarter-by-Quarter Pies

Naturally, the quarter-by-quarter-no-way-these-don’t-work-pies were currently being used by a few people in the room. I adjusted the wording from youth going to detention centers to youth being served so that this example is relevant to even more of you.

The quarter-by-quarter pies are off the table. According to my pie chart guidelines, gender breakdowns are one of the only times it’s okay to use a pie chart (nominal variable, just a few slices, etc.).

But it’s really hard to make comparisons across multiple pies. Your eyes would have to jump from the 1st quarter pie to the 2nd quarter pie to the 3rd quarter pie to the 4th quarter pie and back again. I’m tired just thinking about it.

After

After we sketched ideas and discussed the pros and cons of each approach, we decided that stacked bars with numbers were the most promising. Stacked bars can display the number of males, females, and the totals. They’re also easy to label (compared to, say, a stacked area chart). We used vertical bars because time is ordinal.

My rule of thumb is to display numbers for anything less than 100 and percentages for anything over 100. Fewer than 100 youth went to these detention centers each quarter, so we displayed numbers.

For a Slideshow: Stacked Columns with a Short Title

Here’s the after version for a slideshow:

For a Report: Stacked Columns with a Subtitle

Here’s the after version for a handout or report, which intentionally contains a bit more explanatory text.

Bonus: Make This Yourself

No, I didn’t add the totals to each quarter’s bar chart with text boxes. Yes, that’s possible. It’s also a ton of work to crunch the numbers, create text boxes, and center them perfectly above each bar. This is a stacked bar chart with three segments: males, females, and totals. The total segment has a transparent fill so it looks invisible.

If you want to explore the strategy in more detail, watch the video or download the template.

Bonus: Download the Templates

Purchase the templates ($5)

The post Stop Putting Quarterly Trends in Pie Charts appeared first on Depict Data Studio.

Rules for Using Pie Charts and Donut Charts

Here are my guidelines for using pie and donut charts. Pie charts are okay when they:

1. are well-formatted. No 3D, exploding slices, leader lines, or legends.
2. display nominal variables. Ordinal variables don’t belong in a pie chart.
3. add to 100%. I’ve seen pies that only add to 90% because the designer deleted the “other” category and forgot to recalculate the new percentages.
4. contain positive numbers. I’ve seen designers place a mix of positive and negative numbers inside the same pie chart, which doesn’t make any sense.
5. display a single point in time. Patterns over time belong in a time series graph, like a slope chart, line chart, or dot plot.
6. only have two or three slices. Four slices is pushing it.
7. are displayed individually. Only show one pie chart at a time. No small multiples pies. Comparisons across multiple pies are time-consuming.

Finally, while I don’t consider this to be a strict guideline, pie charts tend to be easiest to read with common fractions, like a one-fourth vs. three-fourths pie or a one-third vs. two-thirds pie.

Circumstances When Pie Charts Are Okay

Given these guidelines, I use pie charts to show:

• male/female/etc. gender categories;
• yes/no survey responses;
• students who graduated high school on time vs. didn’t graduate high school on time;
• adults who live in single-family homes vs. adults who live in other housing types; and/or
• other binary data.

Alternatives to Pie Charts

Let’s tackle these pie charts! It’s not sufficient to tell you to avoid pie charts. You need to know what to do instead. Here are some pie chart makeovers that are inspired by my real projects.

If Your Pie Chart is Poorly Formatted… Then Format It!

The chart on the lower left is poorly formatted. This one is 3D, so the slices look larger or smaller than they really are… and, it’s exploding, which is distracting for viewers… and instead of the percentages being right on top of the pie slices, now there’s a tiny legend down below the pie, which means our viewers would have to zig-zag their eyes around the slide to tell which slice is which.

The final sin in this poorly-formatted pie chart is that there are leader lines, those gray lines connecting the 25% and 75% to their corresponding slices. Plus, So much ink is on the page, yet so little is actually focused on the data.

The well-formatted pie chart on the lower right is fair game. Gender is nominal or categorical, so that works. We’re only showing a single point in time, so that works too. And we’ve only got two different slices.

If You’ve Got Ordinal Data… Then Use a Stacked Bar Chart or a Column Chart

Ordinal or sequential variables have a natural order, like responses to a survey that go from strongly agree to agree to disagree to strongly disagree.

In this case, you’d swap out your pie chart and use a stacked bar chart instead, so that viewers can tell which category is at which end of the spectrum – the agrees on one side and the disagrees on the other side.

Another type of ordinal or sequential variable is age ranges. Histograms are a great alternative to pie charts when you’ve got ordinal or sequential groupings. Let your audience read across the screen from left to right (i.e., from lowest to highest).

If You’ve Got Negative Numbers…Then Use a Deviation Chart

I mentioned that pie charts are only for positive numbers, not negative numbers. Sometimes we have negative numbers when we’re dealing with changes over time.

In this example, we’re looking at four products and whether they increased or decreased in sales compared to the previous quarter. For example, Product A’s sales decreased 20% compared to the prior quarter while Product B’s sales improved 40% compared to the prior quarter.

Instead of a pie chart, we’d use a column chart or bar chart. In your software program, the negative numbers will automatically flip in the opposite direction of your positive numbers. The axis line runs across the middle at 0% and we can see which products went down (like Product A) and which products went up (like Products B, C, and D).

If You’ve Got Patterns Over Time… Then Use a Time Series Chart

What if you have time series data, that is, patterns over time? Maybe you’re trying to show data for each Quarter – Quarter 1, Quarter 2, Quarter 3, and Quarter 4 – or for each month, or for each year in the grant cycle.

Swap out your pie chart and use a line chart instead. You want viewers to see the beginning point – Quarter 1 – over to the end point – which is Quarter 4.

If You’ve Got More than Two or Three Categories… Then Use a Bar Chart

Pie charts are easiest to read with only two or three slices.

What if you have lots of different slices, like favorite ice cream flavors? This pie chart has too many slices – vanilla, chocolate, strawberry, mint, and cookie dough. It’s too hard for our brains to compare the slices to each other.

Swap out the pie chart for a bar chart and order the bars from greatest to least (or least to greatest). Chocolate would be listed first because it’s the most popular, and cookie dough would be listed last because it’s the least popular.

If You’re Tempted to Display More than One Pie at a Time… Then Use a Grouping of Stacked Bar Charts

What if you want to compare several companies, organizations, outcomes, etc. all at once? Pie charts are hard enough to read. Our brains don’t do well deciphering the angles, area, or circumference of circles. Two or three or four different pie charts can be understood, but with way too much mental energy.

In this example, we’re asking our viewers to look first at the 20% angle, and then at the 40% angle, and then their eyes have to zig-zag to the 60% angle, and then their eyes have to zig-zag over to the 80% angle. So. Much. Work.

In this case, you’d swap your small multiples pie chart for a small multiples stacked bar chart. The part-to-whole pattern is still there, but now our viewers’ eyes only have to make a single, diagonal swooping motion down the page to compare all four companies at once. Less energy required for reading, more energy reserved for making decisions based on that data.

Join the Conversation

Have you seen real-life pie charts or donut charts that are in desperate need of a makeover? Comment below and include a link to the example, and I may even include it in a future pie chart makeover blog post.

The post When Pie Charts Are Okay (Seriously): Guidelines for Using Pie and Donut Charts appeared first on Depict Data Studio.