Here’s a quick quiz for all of you aspiring chart experts:
In the chart below, rank the following in decreasing order of value:
- Red wedge
- Orange wedge
- Pink wedge
- Sum of four smaller wedges
The real answer may surprise you (or maybe not).
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Don’t peek until you’ve ranked the data points!
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. . .
Whichever way you have ranked the options, if you tried to eyeball their sizes, you were wrong. Maybe the slight 3D tilt was enough to distort the truth.
Here is the answer key.
It looked to my bleary eye like the sum of the small slices was largest, followed by the orange slice close behind, then the red, and finally the pink. Or maybe the orange is slightly larger than the sum of the four small ones. Either way is wrong. Here are the actual values, in order:
- 301 – Red wedge
- 284 – Orange wedge
- 276 – Sum of four smaller wedges
- 229 – Pink wedge
Another interesting “feature” of this display is its interactivity. When you mouse over a pie segment, it moves away from the other pieces, a leader line is drawn from the pie slice to its legend entry, and a box pops up with some information about the data point.
It’s pretty awkward how the rightmost data point has to reach all the way across the other pie slices to connect to its legend key.
In the bar chart below, rank the following in decreasing order of value:
- Medical Services
- Sum of four smaller bars
You can display this data more clearly in less space if you use a bar chart. The only difficulty is in judging the relative sizes of the three larger bars and the sum of the four smaller bars, but the numbers are there if you need to do some mental math.
You could make this chart interactive by popping up the same info box as is shown in the pie chart, and it would feel just as cool. If you wanted to, you could even highlighted the targeted bar with a darker shade and make its category label bold.
The colorful interactive pie chart above was provided by Discover Card’s Spend Analyzer Demo.