The Lesser known Bullet graph

Tableau is a very versatile business intelligence tool used for creating beautiful visualizations. When I first started learning the different techniques of representing data with this tool, I too like each one of us began with some of the basic charts. Of course they were the bar, line, pie, text chart etc. but slowly when I came to know about some of the advanced charts, I was completely intrigued by the flexibility of Tableau. It offers so many different yet very simple ways to represent data. Let’s look at one of the charts, its use and how to create it.

We will be visualizing how much sales each region has made and how much is it accounting for with respect to the target sales using a Bullet graph. For the ease of generating graphs, let us take an example data set: Superstore. All the charts and graphs below will be created using the Superstore dataset. This dataset has three tables: Orders, People and Returns.

Let’s get started.

A bullet graph is basically a layered bar chart where the background of bars tends to fade out on every growing layer. Bullet graphs are usually used to help the users decide how well or bad the progress is going on for a particular field. Should they be happy or worried about it. If the performance is not up to the mark, then they can take certain steps to improve the execution. For example, if a company wants to find out what were the entire sales in each region of a country and if they are anywhere near the decided target sales, then the analyst can represent such data using this visualization.

To create this, let's assume that the target sales is 1.5 times the sales amount. Create a calculated field Target Sales = Sales * 1.5

We have bullet chart as an option under the Show Me section. To create this, we need two measures. So, for that drag the Sales field to Columns and Target Sales to Rows and then click on Bullet Graphs under Show Me.

Now usually tableau rearranges Target Sales in Columns and Sales in Detail under Marks. But our goal here is to show the trend of Sales against the Target Sales.

So, for this we need to right click on the header and select Swap Reference Line Fields. With this the position of Sales and Target Sales fields will be swapped.

Next, bring in Region field into Rows and there we have the basic bullet chart showing what the sales values are in 4 regions along with the target they were supposed to reach.

By default tableau shows 50% and 75% of target sales indicated by the dark grey and light grey background bars around the blue Sales bar respectively. To edit this graph according to our needs, we can right click on the Sales header and click on Edit Reference lines à 50%,75% of Average Target Sales.

Suppose we want to check how much are the sales with respect to 60% and 80% of the target sales, then we can change these values in Percentages field under Computation. This will give us an idea if the sales are near or have crossed the 60% and 80% of the target sales.

We can also give our graph different fill colors for better readability. Let’s select the Green color.

This is our final Bullet graph.

Similarly, we can create a bullet target graph for Sub-category vs Sales showing the progress towards a target sales value.

For this graph we have to select sales and target sales as measures. Then, after swapping the axis, we need to add sub-category dimension in the rows. Edit the reference lines according to the requirement and voila!

How do we read this graph?

The darker green area in the regional sales chart shows 60% of the target sales and the lighter green shows 80% of the target sales. So, the total sales value for Central region is $501,240 which means that it has crossed the 60% mark which is set on $451,116 but is not even near the 80% mark which is at $601,488. Also, the sales is quite far from reaching the target which is denoted by the black straight line.

How to format the graph?

There are multiple ways in which we can enhance this visualization for better readability.

Labels: In the Edit Reference Line, Band or Box window, we can select Label option as Value. This action will display what should be the sales amount to be achieved or were achieved at the 60% and 80% target marks.

If we select the label option as Computation, then the end of each shaded background is labeled by what is it displaying for easy comprehensibility. Meaning if we select this option then the end of dark green shaded region will be marked as 60% of the target sales and similarly the end of the lighter green background will be marked as 80% of the target sales.

Line: We can add a distinct line to the reference lines, so it is even effortless to look through the shaded backgrounds. this will add a line to the end of each reference line. we can choose this line to be solid or dotted and of whichever line width.

Fill: Lastly, we have the liberty to select a color combination of our choice for the entire chart. Fill Above and Fill Below will add color before and after the reference lines. Symmetric option distributed the colors evenly across the chart. This option however uses only two colors. The Reverse option inverses the color usage.

Symmetric

Reverse

I found this chart very useful while doing the analysis. Very easy to create and even easier to understand, bullet graph is a very good choice if we want to examine the scale of our accomplishments. Hope you have fun creating this visualization!