Switch the Y-Axis for a Metric
You can display multiple metrics on a single graph using two different Y-axes. This is particularly useful for metrics that have different units or that differ greatly in their range of values.
To switch the Y-Axis for a metric
Open the CloudWatch console at https://console.aws.amazon.com/cloudwatch/.
If necessary, change the region. From the navigation bar, select the region that meets your needs. For more information, see Regions and Endpoints in the Amazon Web Services General Reference.
In the navigation pane, click Metrics.
In the CloudWatch Metrics by Category pane, select a category to view available metrics.
Select the check box for one or more metrics.
In the details pane, hover over a line on the graph or the legend entry for the metric and a hover box appears.
Click the switch link in the hover box. The metric switches to the opposite axis.