Steps to reproduce:
1) Create a new stat line with multiple points and some dummy Y values, and make sure the "ranged" box is checked.
2) Click the box for the new and look at the graph to see two lines of points and a gray line between each pair of points.
3) Save stat lines.
4) Close the stat lines window.
5) Re-open the stat lines window.
6) Click on the new stat line ONCE: The values have been zeroed (not saved).
7) Click the box for the new line to display the graph: Exception -> Overflow