A couple possibilities:
You can put the X variable in Group X and turn on the Caption element, choosing N as the caption statistic:
![7275_Screen Shot 2014-09-13 at 3.47.09 PM.png 7275_Screen Shot 2014-09-13 at 3.47.09 PM.png](https://community.jmp.com/t5/image/serverpage/image-id/814i6A2DE47D16D72279/image-size/medium?v=v2&px=400)
Or you could make an computed character variable that represents the count and nest it inside of the X variable:
![7276_Screen Shot 2014-09-13 at 3.51.32 PM.png 7276_Screen Shot 2014-09-13 at 3.51.32 PM.png](https://community.jmp.com/t5/image/serverpage/image-id/815iD317D1E66E15C5C9/image-size/medium?v=v2&px=400)
And in case it doesn't go without saying: you can always manually add text annotations or a custom graphics script if you need maximum flexibility.