When there are two sets of data, each follows a different scale, and they are related – we create a chart with a Dual Axis. These charts are useful for comparing one series with another, for example, to compare income and tax. It is also possible to use more than two axes.
To compare two series that share a common axis we use Combination Charts.
In this article we show how to create a Dual Axis Chart in Contour Reporter.
Let's say we would like to show the average temperature in Tokyo and compare it to the average rainfall over the same period of time.
To do so, we need to create a chart showing a relation between the two variables, because they are in some way related. In Contour Reporter, such information can be displayed using a Combination Chart with a Dual Axis.
A Dual Axis means that the measurement variables possess units that are different but somehow related and are therefore displayed with a secondary axis.
For this example, we use tables of Monthly Climate Statistics from the Japanese Meteorological Agency downloaded from ( here).
We create a full project and then add a chart.
- Load the data to the database and create an OLAP report
- One way to organize data in the Grid is to keep the Month dimension in rows, Year in the filter area and the two facts
- Then we add a Chart to the slice. Select Combination
- Set the Grid to Master View and synchronize on facts
- Set Chart properties to display information. These are our settings:
- The chart caption reads as follows: Monthly Temperature and Precipitation in Tokyo - [number-format:# ##0]years [pos:first][Year] until [pos:last][Year] (see topic Macros for details)
- Then we set two different chart types within the Combination Chart. We display the temperature as Line and the rain fall as Bar.
- To do so, from the chart toolbar, click the Stylesheet button – Fact Styles
- Click the Temperature fact
- In the Stylesheet dialog for the Temperature fact, set values for Chart Color and Properties, Type
- As already mentioned, for this fact we choose the Line type from the list
- Repeat the process for the Precipitation fact, select Type Column
- Finally, we need to set the chart to display the dual axis
- In this example, we do so for the Precipitation fact
- In the dialog displayed in the figure above (step 11), check Style Axis
- Check Visible, so that the axis for this fact is displayed. It will be displayed at the right of the chart
- Finally, we have the resulting chart: