How to Add a Second Y Axis to a Graph in Microsoft Excel

Adding a second Y-axis to a graph in Microsoft Excel can be useful when you want to compare two different sets of data that have different scales. Here are the steps to do this:

1. Select the data you want to graph. 2. Click the "Insert" tab at the top of the screen. 3. In the "Charts" section, click on the desired chart type, such as "Line" or "Column." 4. Excel will automatically create a chart with one Y-axis. 5. Right-click on the data series you want to add a second Y-axis to, and select "Format Data Series" from the drop-down menu. 6. In the "Format Data Series" pane on the right-hand side of the screen, select the "Series Options" tab. 7. Check the box next to "Secondary Axis" to add a second Y-axis to the chart for that data series. 8. Repeat steps 5-7 for any other data series you want to add a second Y-axis to. 9. To format the second Y-axis, right-click on it and select "Format Axis" from the drop-down menu. 10. In the "Format Axis" pane, select the "Axis Options" tab and customize the scale, labels, and other settings as desired. 11. Repeat step 10 for the primary Y-axis if needed.

That's it! Your chart now has a second Y-axis for the selected data series. You can customize the formatting and design of the chart further by using the various options in the "Chart Tools" tabs that appear when you select the chart.