You can see and change the most commonly changed options for each block using the icons in the block list: 
Click the Invert icon 
to flip the y-axis of the plot. This may be useful to monitor blocks that are inversely related. The icon will show an arrow pointing up normally, and an arrow pointing down if the plot line is inverted. This can also be accomplished by selecting Block | Reverse Y-Axis, or selecting Reverse Y-Axis from the block's context menu.
See also
- Adding a block to a group
- Adding a live loop annotation to the watch window
- Automatically generating the best range for plots in the Watch Window
- Changing plot line colors in the Watch Window
- Changing the update interval for blocks and groups in the Watch Window
- Deleting a block from the Watch Window
- Editing a block in the Watch Window
- Managing Blocks in the Watch Window
- Pausing data collection for a block in the Watch Window
- Rearranging blocks in the Watch Window
- Saving the current plot vertical range as the custom range
- Setting the update interval for a block in the Watch Window
- Showing/Hiding a plot line in the Watch Window
- Understanding when data points are connected with lines in trend plots
- Automatically generating the best range for plots in the Watch Window
- Changing plot line colors in the Watch Window
- Changing the horizontal or vertical plot resolution
- Changing the update interval for blocks and groups in the Watch Window
- Controlling Data Display in the Watch Window
- Navigating Watch Window data with the Navigation Timestrip
- Preventing pink-colored out of range data from appearing on Watch Window plots
- Setting a plot display start time
- Setting the plot font size
- Showing/Hiding a plot line in the Watch Window
- Stopping the plot from scrolling in the Watch Window
- Understanding when data points are connected with lines in trend plots
- Viewing the Watch Window as one plot or split plots