We often find ourselves needing to compare multiple measures in a single chart, one way we can do this is by using a dual axis chart. Now the clue is in the title here, dual means we can compare two measures using two different axes. So, how are they created?
Method 1
Set up your first measure in the view, for example we have Date in columns and Sales in rows
Now with your next measure, drag and drop the field onto the opposite side of the chart to the axis until you see a single green bar
Make sure to right click and Synchronise Axis otherwise your measures will be on different scales and the overall message of the chart can be misleading for example the chart below doesn't make much sense since sales should always be higher than profit, so always remember to tick this option
And there we have it! A dual axis chart. See how on the rows shelf, the two measures have straight edges facing each other, this is to indicate we have a dual axis between them
Method 2
Start off with just your first measure in the view, same as method 1 but instead of dragging the second field onto our view, drag it onto the rows shelf
So now we have one chart for each measure, but we want them on the same chart so we can do this if we right click on the second measure's axis and tick Dual Axis
Once again remember to synchronise. Sometimes measures can be compared on different scales but it's important to make that clear so that any insights drawn from the chart will be accurate.
So there we have two ways of creating a dual axis chart!
Pros:
- Each measure will have it's own marks card giving lots of flexibility in the chart design e.g. this way we can build a bar chart with an overlaying line chart
Cons:
- You can only have a maximum of two measures to compare
So now you know how to build a dual axis chart multiple ways! As stated above, the limitation of this chart is that you can only compare two measures, so what if you had another you wanted to compare? There is another type of chart we can use for this... the combined axis chart
