You can set various chart options by clicking on the "Chart options" header in the panel to the left.
Show series data: Displays the corresponding value next to columns and bars in the chart.
Show trend line: The trend line will visualize how your data evolves over time - e.g. is performance improving or detoriating. Makes sense when periods are selected as category.
Hide chart subtitle: Hides the title and subtitle of your chart.
Hide chart legend: Hides the legend and leave more room for the chart itself.
Domain axis label: Displays a label below the domain axis (also referred to as the X axis). Can give context information to the chart, e.g. the type of periods being listed.
Range axis label: Displays a label next to the range axis (also referred to as the Y axis). Can give context information to the chart, e.g. the unit of measure being used.
Target line value: Displays a horizontal line at the given domain value. Useful e.g. when you want to compare your performance to the current target.
Target line label: Displays a label next to the target line.
Base line value: Displays a horizontal line at the given domain value. Useful e.g. when you want to visualize how your performance has evolved since the beginning of a process.
Base line label: Displays a label next to the baseline.