This article explains how to add a secondary axis to a chart in Excel so you can view unlike categories on the same graph. These instructions work in Excel in Microsoft 365, Excel 2021, Excel 2019 ...

Excel automatically distributes these points along a uniform X axis. To add more data to the Y axis in a line chart, add additional numbers in cells below your existing data.

How to Add a Second Y-Axis on Excel & Make a Second Series at the End of the Chart. Microsoft Excel charts give you a large number of options for displaying the data in your spreadsheet.

We discuss a comment on a previous post stating that the text of labels on the vertical axis of graphs must be horizontal by discussing the pros and cons of four possible positions for these labels.