You can use ODS Graphics
Editor to add the following annotation objects to a graph:
text annotations
lines and arrows
ovals (and circles)
rectangles (and squares)
markers
images
The annotation objects
are rendered on top of the graph. Unlike titles and footnotes, annotation
objects do not cause a graph to be resized or rearranged.
Annotation objects can
be attached to a graph data points. If the graph is resized, the annotations
move with the data point. For more information, see Understanding Annotation Objects and Data.