I wouldn't be surprised if there were multiple ways to implement this. The one that comes most immediately to mind is using table calculations. A calculated field identifies the top 3 and bottom 3 using LAST() and FIRST(), then that field is used as a filter in your chart. See the attached workbook for details.
scatterPlotHelp2.twbx 42.6 KB
Thank you for your solution.
I will spend some time understanding it.
At first glance it appear you have defined the first and last 3 off ID.
Ideally I am looking for it to be based off Sales1 and not ID. This is harder as Sales1 is considered a measure by default.
Could you offer an guidance?