Combo Charts and Secondary Axes

Combo charts combine two chart types in one visualization. They are used when two data series have different scales but need to be shown together. A common example is: revenue (large numbers) and conversion rate (percentage).

If both are plotted on the same axis, one series becomes unreadable. A secondary axis solves this.

Creating a Combo Chart

1. Select the dataset with multiple numeric series;
2. Go to Insert;
3. Choose Combo Chart;
4. Assign different chart types to each data series;
5. Enable Secondary Axis for the series with a different scale.

Excel will display one axis on the left and another on the right.

When to Use a Secondary Axis

Using the provided dataset:

• Insert a Combo Chart;
• Set one series as a Column Chart;
• Set the second series as a Line Chart;
• Enable a Secondary Axis for the line series.

Goal: display both series clearly despite different value scales.