Bullet charts came into existence to overcome the drawbacks of Gauge charts. We can refer to them as Liner Gauge charts. Bullet charts were introduced by Stephen Few. A Bullet chart is used to compare categories easily and saves on space. The format of the Bullet chart is flexible.
According to Stephen Few, Bullet charts support the comparison of a 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 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 the Gauge charts.
Consider an example given below −
In a Bullet chart, you will have the following components −
|30% - 60%||Fair|
|60% - 80%||Good|
With the above values, the Bullet chart looks as shown below.
Though we used colors in the above chart, Stephen Few suggests the usage of only Gray shades in the interest of color-blind people.
Bullet charts have the following uses and advantages −
Bullet Charts are widely used by data analysts and dashboard vendors.
Bullet charts can be used to compare the performance of a metric. For example, if you want to compare the sales of two years or to compare the total sales to a target, you can use bullet charts.
You can use Bullet chart to track the number of defects in Low, Medium and High categories.
You can visualize the Revenue flow across the Fiscal year.
You can visualize the expenses across the Fiscal year.
You can track Profit%.
You can visualize customer satisfaction and can be used to display KPIs also.
Arrange the data as given below.
As you can observe, the qualitative values are given in the column – Performance. The Bands are represented by the column – Value.
Following are the steps to create a Bullet chart −
Step 1 − Select the data and insert a Stacked Column chart.
Step 2 − Click on the chart.
Step 3 − Click the DESIGN tab on the Ribbon.
Step 4 − Click Switch Row/ Column button in the Data group.
Step 5 − Change the chart type.
Step 6 − As you can see, the Primary and the Secondary Vertical Axis have different ranges. Make them equal as follows.
Step 7 − Deselect Secondary Vertical Axis in the Chart Elements.
Step 8 − Design the chart
Step 9 − Right click on the column for Value (blue color in the above chart).
Step 10 − Select Format Data Series.
Step 11 − Change Gap Width to 500% under SERIES OPTIONS in Format Data Series pane.
Step 12 − Deselect Secondary Vertical Axis in the Chart Elements.
The chart will look as follows −
Step 13 − Design the chart as follows −
Step 14 − Fine tune the chart as follows.
Step 15 − Fine-tune the chart design.
Your Bullet chart is ready.
You can change the color of the chart to gray gradient scale to make it colorblind friendly.
Suppose you want to display the number of defects found in a Bullet chart. In this case, lesser defects mean greater quality. You can define defect categories as follows −
Step 1 − You can then define a Limit for number of defects and represent the number of defects found by a Value. Add Value and Limit to the above table.
Step 2 − Select the data.
Step 3 − Create a Bullet chart as you have learnt in the previous section.
As you can see, the ranges are changed to correctly interpret the context.