How To Customize The Dashboard Metrics
You can choose which metrics you want to show up in the Metrics bar and in all tables across all dashboards.
These are the Metrics that are visible by default on all dashboards: 
You can click on the metric selector button and then choose to turn on or turn off any of the metrics.
For example:
Also, your metric selection affects the columns that appear in the table further down the page too:
To quickly restore the default list, click on the red Clear All button:
To quickly select all the metrics, click on the green Add Filtered button: