Chandoo: Did somebody just chart?
Jeff: Yes. Yes I did. More on that later. But first, let’s take a sniff of Mike Alexander’s outliers, shall we?
Over at the bacon bits blog, Mike has an interesting post on using something called the Tukey Method to identify outliers in a data set. That article is worth reading for John Walkenbach’s comment alone.
Here’s Mike’s sample dataset, with the data points identified as outliers highlighted in orange:
The Tukey method that Mike blogs about constructs a fence around “reasonable” readings, and that fence is described mathematically by an arbitrary numerical factor:
(Quartile 1) – (Arbitrary_Factor × IQR)
(Quartile 3) + (Arbitrary_Factor × IQR)
Typically a factor of 1.5 is used. Check out Mike’s blog for a detailed explanation of this stuff.
That’s all good, but it also produces a fairly arbitrary cut-off, depending on what factor you use. So rather than using an algorithm to determine outliers, my preference is to sort the data from lowest to highest value, then plot it and look at the resulting shape:
—Edit— Jon says in the comments:
Your line chart would be easier to read if you’d used markers. I use markers to indicate where the data actually IS, and help show that the line only ties the data together and doesn’t indicate more data, until the points are nearly touching.
Trust Jon to chart in my face. But he’s right. So here it is:
[Aside: That chart’s done in Excel 2013. What’s weird is that those markers aren’t centered on the line, but seem to sit just above it by a point or two. Whoops, Microsoft.]
And here it is with data labels, so it’s easier to see the actual values:
Some may say that the data labels are redundant, because you can gauge the values from the axis. My mature response to that is “Ffffffrrrrrt”. I like the data labels…once I’ve used the line to quickly judge what may be outliers, the labels let me confirm the jump in values without having to move my head back and forth like I’m watching Roger Federer play Andy Murry at Wimbledon.
In fact, maybe I can combine the marker with the labels, and get rid of that axis altogether:
Hey, that looks cool. Anyone going to get Tufte on me?
—Edit over—
This is akin to making a bunch of actors line up in order of shortest to tallest, and saying:
Okay…Elijah, Dominic, Billy, and Sean…you’re shortest. And by golly, you four look a lot shorter than the others. You guys can be the Hobbits.
[Aside: I recreated the below graph from one a site called SFScope. Check out the outliers at both ends, and click on the picture to visit the original]
I like this graphical approach. I think it takes less effort to visually identify outliers than to programatically identify them. For instance, let’s look at Mike’s sample data again for a moment:
Looking at this data, I visually identify pretty much the same outliers as Tukey would – points 1,2,3, 19, and 20. In addition, it looks like that 4th data point – with a value of 13 – looks like it has outlier stamped all over it too, when you see it in context of the other data.
Another benefit of plotting ranked data is that it also allows you to ask questions about interesting trends within the datapoints that clearly are not outliers. For instance, what’s the deal with the sudden ‘acceleration’ in the trend between datapoints 16 and 17 caused by? Understanding drastic changes within non-outlier points might be worth as much money to a business as understanding the outliers themselves.
Lose the horizontal axis?
Sometimes with larger datasets, that horizontal axis can be distracting, because Excel only has enough space along that axis to display the labels for every nth rank.
For instance, take the below graph, which looks at just how much money an organization receives from each of its customers by way of annual membership subscription each year:
See what I mean? You find yourself trying to decipher the trend in the data labels, and this really draws your eye away from the incredible trend shown in the graph above.
So let’s just delete them:
That’s much less distracting. Wow: many of our customers hardly subscribe to anything, and a few practically keep this place afloat!
What else can we show on a graph like this?
Sorting your data like this also lends itself to visually segmenting your customers by how much they contribute to your total revenue.
For instance, the below graph shows just how many customers it takes to account for each subsequent 25% of revenue, and what the average annual subscription within each group is. This gives you a real appreciation into just how valuable your larger customers are in comparison to smaller customers:
Wow, half our subscription revenue comes from our Key Accounts and Large Customers groups, who make up just 10% of our subscription base. Let’s be especially nice to those customers. And lots of our effort is spent in servicing small clients that don’t buy much. Can we grow their business? Should we sack some of them as customers, so we can spend that effort finding bigger ones?
Using revenue ‘buckets’ of 25% was a fairly arbitrary choice. What if we designed a chart template that let you dynamically choose different sized revenue buckets, as well as let you use more buckets if you wanted to?
For instance, looking at the above graph, it looks to me that we have a whole bunch of ‘Tiny Customers’. And we also might want to segment that group of Median customers that all have exactly the same sized subscription into a group of their own.
Well, the chart template I’ve put together for this post lets you do just that:
Wow. Jeff charted again. Man, look at all those time-wasting small accounts…they’re about as welcome as a chart in an elevator!
Note that the above graph was produced using Excel 2013. Excel 2013 automatically puts in those grey lines connecting the data lables with the series. Those are called Leader Lines. They rock.
Unfortunately, earlier versions of Excel only use leader lines for pie charts. But fear not, intrepid reader, for my chart template uses a bit of VBA to automatically puts lines in for you using shapes, if you’re using Excel 2010:
What’s cool about this template is that all the data labels are dynamic: change the ‘breakpoints’ between groups or the number of groups in the ‘Controls’ table [see screenshot below], and the details within the data labels are updated automatically. Bing!
I modified a version of Jon Peltier’s great Label Last Point routine to refresh the placement of the data labels. (Thanks, Jon). Here’s the template, so you can play around in the privacy of your own screen:
Segmenting customers by revenue contribution_V1 [Not tested in Excel 2007 or earlier]
Oh yes. I most definitely charted, boss.
Updates
—Update 1—
Prompted by some great action in the comments below, I whipped up this redesign in both gray and white:
While I like the grey, I do think it’s harder on the eyes than black text on white background. And I don’t think a grey chart would work well on say a dashboard. But that said, there’s no doubt in my mind that this chart is sexier than my original. Might look nice in the Economist. Here’s a link to the revised sample file: Segmenting-customers-by-revenue-contribution_with_Leader_Lines V1
—Update 2—
Kaiser Fung has some great ideas on how to redesign this in his post Visualizing Uneven Distributions. Go check it out, and be sure to subscribe to both his Junk Charts blog as well as his Big Data, Plainly Spoken blog. Both are gold. Both will make you a better analyst.
Added by Chandoo
If you like this chart, chances are you are going to love the below too:
39 Responses to “Make a Quick Thermometer Chart to Compare Targets and Actuals”
You'll probably have some readers insist on bullet charts, which in my experience are no easier to read.
Note on the case where actuals may exceed targets, the target has to be the second series in the chart, not the first, so it appears in front of the actual.
@Jon.. good point. And yes, readers are already saying bullets are the way to go. Atleast @dmgerbino said it on twitter: http://twitter.com/dmgerbino/status/6761754333
But I feel the same as you did. Bullets need orientation to get started and not that easy to construct (here is a tutorial btw... http://chandoo.org/wp/2008/07/21/dashboard-bullet-graphs-excel/ )
When you just have to compare 2 sets of values, a chart like above is good and easy enough.
And yes, thank you for saying that data series order should be correct to show the target on top.
I think bullet charts are a good alternative. I'm not a huge fan of the formatting that you used above where the outline is so thick.
Another option would be to combine a line graph (plan/goal amounts) with the columns (actual) and select the option to remove the line. This leaves just the value (marker), which can be increased in size to leave only a line about the size of the bar. It's an easy and cleaner way to show actual to plan/goal. Does that make sense?
Tony -
I would use columns (or area) for goal, and lines and markers for actual.
What about if you go over the target? The chart doesn't work so well then.
The technique described today is a near bullet chart. As I stated early this morning on Twitter (link: http://bit.ly/4K3yPM ) , I am a fan of Stephen Few's Bullet Graph.
Hubert Urruttia and I started with Charlie Kyd's method, but as Jon Peltier and Chandoo said, they are not easy to contruct. We moved onto prototyping with Fabrice Rimlinger's SPARKLINES FOR EXCEL and now use XLCube's (BonaVista) Micro Chart tool. Both of these tools allow you to create bullet charts just as easy as any Excel chart type.
As far as reading and interpreting them, this chart type has been the easiest for us to present.
There are many chart types. Today's "Make a Quick Thermometer Chart to Compare Targets and Actuals" is fine for a start, but your ultimate goal should be to create Bullet Graphs. AS Stephen Few states in his overview, "The bullet graph was developed to replace the meters and gauges that are often used on dashboards. Its linear and no-frills design provides a rich display of data in a small space, which is essential on a dashboard. Like most meters and gauges, bullet graphs feature a single quantitative measure (for example, year-to-date revenue) along with complementary measures to enrich the meaning of the featured measure. Specifically, bullet graphs support the comparison of the featured measure to one or more related measures (for example, a target or the same measure at some point in the past, such as a year ago) and relate the featured measure to defined quantitative ranges that declare its qualitative state (for example, good, satisfactory, and poor). Its linear design not only gives it a small footprint, but also supports more efficient reading than radial meters."
@dmgerbino
Since @dmgerbino had to bring my name up I guess I should throw in my two cents.
@dmgerbino and I have both implemented Bullet Charts with great success. What is most interesting about this fact is that we have had a harder time implementing Sparklines than Bullet Charts. The reason for this revolves around the simple fact of familiarity. I will explain. People look at a Sparkline and they think it is a really small Line Chart and it is not. People are familiar with Line Charts since they have been around since 1786 when they were created by William Playfair. Bullet Charts on the other hand are different so they almost demand an explanation. Because of this there was a lot of face time that was needed to explain these charts but once people got them they understood the concept. This is similar to when I introduced Cycle Plots http://bit.ly/87ydVG (Thank you @nbrgraphs!) or Horizon Charts http://bit.ly/6PVavj.
Now about the Thermometer Charts… The first thing I want to address is Tony Rose’s statement. I totally agree that the outline on the chart is too think. It might come of as being a whole new series or a new variable. What I have done in instances like this is I have created a Bar Graph and Scatter Plot mixture. Then I have turned off the Data Series on the Scatter Plot and turned on the Horrizontal Error Bars on the Scatter Plot. The new horizontal line stands for the Plan and the Bar is the actual. The reason why I find this more useful is because this technique works if you have exceeded plan. Actually, I do not understand how Chandoo’s method would display the data if Plan is surpassed.
This reminds me of another blog post that @dmgerbino, @Jon_Peltier, and myself commented on over a year ago. http://bit.ly/PNdO Actually, I talk about similar things in regards to familiarity to charting techniques.
- @hubert_urruttia
[...] we have a post on using thermometer charts to quickly compare actual values with targets. Today we follow up the post with 10 charting ideas you can use to compare actual values with [...]
Hi Chandoo
How do I increase the width of the bar chart and also make the long axis labels come in the same line?
Thank you,
Rajiv
@Rajiv
Select the outer part of the chart "Chart Area" and note the cursor will change to arrows
drag the edges to what ever size you want
You can hold the Alt key as you drag and the chart will snap to the cell boundaries
Now click on the chart area inside the chart "Plot Area" and note that a box with small circles appears around it
drag the circles on the edge of that box to suit
You can hold the Alt key as you drag and the chart will snap to the cell boundaries
@ Hui
Thank you for your comments. But my question was not for the "Plot Area" instead I wanted to know about how should I increase the width of the individual bar charts because with my data all the individual bars are coming to be thin and I want to make them appear broader.
Thank You
@Rajiv
Right click on the Series you want to change and select Format Data Series
Under Series Options goto Gap Width and decrease it to suit
[...] Make a Quick Thermo-meter Chart using Excel [...]
Thank you for the great chart and explanation!
How do I show two amounts (Signed Revenue and Pipeline) as stacked within the Target amount?
@CL... you can use stacked column charts and follow the same technique to get this. See attached file for an example - http://img.chandoo.org/playground/thermo-meter-with-additional-details.xlsx
Chandoo - thanks for the quick response! What if I want the data label for the pipeline to be the actual pipeline value, not the signed rev + pipeline value? i.e. 15 instead of 55
Thanks!
How would i do this in excel 2003?
[...] Thermo-meter charts are very good to show how actual value compares with target (or budget). But how can we add another point for say Last Year value to the chart with out cluttering it. [...]
Hi Guys,
As Matt said,
"What if you if you go over the target?"
Is there a way to make it change color? or at least to show what the target was?
I am planning to use this with a "Forecasted vs Real" production chart but I do not know how to show overproduction.
Any clue?
Thanks
How do I do this if I have 2 bars I want side-by-side? ie 2012 Mean with 2012 benchmark overlapping and then 2013 mean with 2013 benchmark overlapping? I want the 2012 and 2012 mean bars sie by side to compare multiple categories.
Sorry, I meant to say the 2012 and 2013 mean bars side by side
I have a problem in that my PM wants a chart that shows a stacked column (Labor and Expense) and then have the overall buget shown as a thermo.
Everytime I try to do this, I either end up with all three being stacked or all of them being seperated.
Help?
Or if someone knows how to only outline the top and sides of a chart series....then I would have this solved. (Make a stacked column with labor, expenses, and remaining budget, then clear the fill and outline only the top and sides.) I just can't figure out how to do that/ not sure if excel will let me only outline part of a chart series.
[...] Thermometer chart to show budget vs. actual performance [...]
Your home is valueble for me. Thanks!...
I've created the thermometer chart as the Chandoo tutorial described. How do I move my columns closer together? I don't want wider columns; I want to move my narrow columns closer together. Thank you!
Dear Elite members,
could you please let me informed whether we could incorporate color formating in this thermometer approach i.e. if my actual performance is <Min then meter color sud go Red, in between min & target it sud change to Amber & target and above sud change to Green. pls advise. thanks,
I think the only way to do that would be with VBA programming.
@Abhinav
Yes, Simply use a stacked column chart, colored appropriately
Or
You may also want to read about Bullet Charts
@ Hui,
Could you pls demonstrate this with the help of an example.
let's have the below sample data
Actual=12
Min=10
Target=15
Max=20
if Actual>=Min then bar color sud be Red
in between Min & Target= Amber
between target(inclusive) & Max = Green
greater than or equal to Max= Blue
Thanks in advance
Abhi
Great blog post with awesome sample data. I've implemented two of the top "power tips" by changing the colour of the actual values, AND setting Actual to be 40% transparent. Looking good.
[…] easy with these charts. Use them sparingly. As a rule a thermo-meter chart would be better (easy to make, takes less space, scalable) for situations like […]
[…] easy with these charts. Use them sparingly. As a rule a thermo-meter chart would be better (easy to make, takes less space, scalable) for situations like […]
I recently purchased the template bundle and love the ease of use - thank you!
I would like to ask if it is possible to add an important 'block' to the dashboard to illustrate an important status for my executive team; 'billing status'? (ie budget / amount billed) something like that?
Thank you!
@Cheif449.. Thanks for your purchase and kind words.
You can add this easily to the dashboard. Follow below steps.
1. Unprotect the dashboard worksheet.
2. Add a text box (Insert > Drawing Shapes) to the dashboard
3. Put any text inside it as per your need.
4. Format it as needed.
5. Protect the dashboard again.
How do you do this in Excel 2010 - I am not seeing that option in Format data series.
how would we check target and actual sale for multiple years
Select any of the bar, right click and format data series