Adding a goal line can be helpful in measuring your progress towards your goals. While your key value shows a snapshot of your actual performance, the goal line is a visual line on your metric that lets you compare your performance against your goal.
To add a goal line, go into the Edit Metric view for one of your metrics. If you are creating a new metric, you’ll want to connect your data, then start building your metric visual before adding a goal line.
In the Settings section at the bottom of the left side, click on "Goal Line."
You’ll have two options for the goal line. You can either type in a value for your goal line, or you can select a specific cell for your goal line. This may be a value within your data, or you could use Spreadsheet Functions to create a specific goal line.