Introduction

Dual Axis refers to the fact that we have two axes over the same graph. An axis is a very important component of any graph, and it represents the quantitative measure based on which visualization is created. Dual axis charts help in presenting plenty of information in the limited space present on your dashboard and can also be applied to build creative graphs such as “Lollipop chart”, “Bullet chart” etc.. Here are some examples of 3 types of Dual Axis Chart.

1/ Dual Axis Charts including reference line and Parameters

The example below provides information on sales vs benchmark over 5 years.

  • Drag Date in columns and change it to measure by selecting month
  • Drag sales measure twice into Row
  • Right click on Sales and select Dual Axis
  • Right click on Axis “Y” and select Synchronization
  • Add a Parameters :
    • Select data type Float / Add a value / Custom display format if required
  • Add a reference line :  Right click on Axis “X” and select add reference Line
    • Under “Scope” select entire table / Under “Value” select Parameters that was created / Custom label and tooltip and add value
  • Create a calculate field to display what is above or under benchmark such as :
    • If SUM([Sales])> [Sales benchmark ] then “Above benchmark” else “Below benchmark” END
  • Drag the calculated field into the Marks under Sales 2 in the color. Change Graph to be Circle
  • Format the table by removing Lines, ” X” axis on the right etc…

2/ Lollipop Chart 

The lollipop chart is a composite chart with bars and circles. It is a variant of the bar chart with a circle at the end, to highlight the data value.

  • Steps are the same except that  Parameters , Reference line and Calculated field are not used in this example
  • The only difference is the format of the graph for each measure
    • For Sales select Bar chart and play with the size
    • For Sales 2 select Circle Chart and play with the size

3/ Bullet Chart 

A bullet chart is a variation of Bar chart. In this chart, we compare the value of one measure with another measure in the context of finding the variation in the first measure within a range of variations in the second measure.

For this example I used two different measures : SUM of Sales and Profit

  • Steps are similar except that Parameters , Reference line and Calculated field are not used in this example.
  • Change format of the graph for each measure
    • For Sales select Bar chart and play with the size
    • For Profit select Gantt Bar

Start using Dual Axis chart to demonstrate the relationship between two different variables . It can help identify insights that you might miss with standard charts.

Olivier Gouet
Author: Olivier Gouet