If your reports include hourly distribution of data like,
- Customer footfalls in your store
- Page views of your site
- Customer service calls to your toll free numbers
here is an interesting charting idea to show the data around the clock (literally)
Update: Visualization pros Jon Peltier and Jorge Camoes took a critical look at this, nearly fainted 😉 at the carnage of a familiar metaphor and posted their awesome reviews here:
Rock around the clock by Jon, he recommends a line chart over this for all the valid reasons
Charting around clock by Jorge, he suggests a neat looking 12 pointed radar chart as an alternative.
Both these are indeed fine examples of how shaking a familiar metaphor (analog clock) or way doing (usual bar chart for 24 hours) can bring a great discussion and excellent alternatives out of passionate people. Do read them 🙂
What you are seeing is essentially 2 bubble charts tweaked to look like wall-clocks with bubbles around the 12 positions.
This can be an interesting addition to your dashboards or daily report. Excited to find out how this is done? read on.
1. Get your data ready to plot it around the clock (circle)
Let us build the above graph using fictitious page view data for each of the 12 hours since midnight till noon. The data is shown aside.
In order to create the around the clock affect we need to plot each of these hourly values around a circle at 12 points. Now, without getting all mathematicky to scare you, lets try to come up with simple explanation to find all the 12 points around the circle:
Assuming the radius of clock or our chart circle is 100,
- Clock has 12 hour positions, thus each one is 30° (360°/12)
- The first point’s x value would be:
SIN(30°)*100 - and y value would be:
COS(30°)*100 - For each of the other 11 points, we just need to use the multiples of 30: 60, 90, 120, .., 360
- in excel spreadsheet you can find the values by
ROUND(SIN(RADIANS(hour*30))*100,0), ROUND(COS(RADIANS(hour*30))*100,0) - We have to convert the degrees to radians since SIN(), COS() accept only radians as inputs
Once we are done, the data should look like this:
2. Plot the Bubble Chart
This is the easy part, just select the cells containing x,y and page view values and insert new chart, select bubble as the chart type. Make sure you have mentioned the x,y, and bubble sizes in correct places.
The fun part begins after creating the chart, as the dimensions may be skewed and you may get egg like circle, so adjust the dimensions and your 12 hour clock view is ready to go.
Use the same process to create another clock for hours from noon till midnight and juxtapose them on that dashboard or report, send it across to your boss or team, let the conversation begin 😀
Download the template and play with it
Like this technique, why don’t you download the Data Around Clock – Charting Idea excel and play with it. Its available on the standard PAHF license (Poke Around, Have Fun)
Fun ways to enhance these charts:
- Overlay a clock diagram in the background
- Use sky color for the background, thus one clock has darker shades and other has brighter shades
- Bubbles themselves can be colored as Sun colors, bright orange to yellow and back to orange
More on Bubble Charts: Why you should star retirement savings really early, Olympic Medals per Country in All Years
More on charting: Hack together a thermometer chart, tell a story with min-max charts, 73 awesome chart templates, download and wow
14 Responses to “Group Smaller Slices in Pie Charts to Improve Readability”
I think the virtue of pie charts is precisely that they are difficult to decode. In many contexts, you have to release information but you don't want the relationship between values to jump at your reader. That's when pie charts are most useful.
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Chandoo,
millions of ants cannot be mistaken.....There should be a reason why everybody continues using Pie charts, despite what gurus like you or Jon and others say.
one reason could be because we are just used to, so that's what we need to change, the "comfort zone"...
i absolutely agree, since I've been "converted", I just find out that bar charts are clearer, and nicer to the view...
Regards,
Martin
[...] says we can Group Smaller Slices in Pie Charts to Improve Readability. Such a pie has too many labels to fit into a tight space, so you need ro move the labels around [...]
Chandoo -
You ask "Can I use an alternative to pie chart?"
I answer in You Say “Pie”, I Say “Bar”.
This visualization was created because it was easy to print before computers. In this day and age, it should not exist.
I think the 100% Bar Chart is just as useless/unreadable as Pies - we should rename them something like Mama's Strudel Charts - how big a slice would you like, Dear?
My money's with Jon on this topic.
The primary function of any pie chart with more than 2 or 3 data points is to obfuscate. But maybe that is the main purpose, as @Jerome suggests...
@Jerome.. Good point. Also sometimes, there is just no relationship at all.
@Martin... Organized religion is finding it tough to get converts even after 2000+ years of struggle. Jon, Stephen, countless others (and me) are a small army, it would take atleast 5000 more years before pie charts vanish... patience and good to have you here 🙂
@Jon .. very well done sir, very well done.
good points every one...
I've got to throw my vote into Jon's camp (which is also Stephen Few's camp) -- bars just tend to work better. One observation about when we say "what people are used to." There are two distinct groups here (depending on the situation, a person can fall in either one): the person who *creates* the chart and the person who *consumes* the chart. Granted, the consumers are "used to" pie charts. But, it's not like a bar chart is something they would struggle to understand or that would require explanation (like sparklines and bullet graphs). Chart consumers are "used to" consuming whatever is put in front of them. Chart creators, on the other hand, may be "used to" creating pie charts, but that isn't an excuse for them to continue to do so -- many people are used to driving without a seatbelt, leaving lights on in their house needlessly, and forwarding not-all-that-funny anecdotes via email. That doesn't mean the practice shouldn't be discouraged!
[...] example that Chandoo used recently is counting uses of words. Clearly, there are other meanings of “bar” (take bar mitzvah or bar none, for [...]
[…] Grouping smaller slices in pie chart […]
Good article. Is it possible to do that with line charts?
Hi,
Is this available in excel 2013?