The Scatter plot has a DataLabel role in the "Assign Data" that you can use to display a value in the graph. Series plot does not have this, but you can overlay the scatter plot on top of the series plot and use this feature. You can set the scatter marker size to Zero. If you want to see the value "exactly" at the center of the location, you can with SAS 9.3. In Plot Properties, "Data Label" tab, set the Position to 'Center'.