Format of the X value in tooltip:
Add your custom String :
Formatting text of the mouseover hints. Move the mouse cursor over the bubbles to see the multiline hints. To change the format of the displayed data point values use the controls to the right. This example also allows you to do Zoom/UnZoom.
To UnZoom click at the bottom right of any area on Chart, drag and release mousebutton at the top and left of the first click.
To Zoom click at the top left of the area you wish to zoom, drag and release mousebutton at the bottom right of zoom area.