The characteristics of custom column grid labels are:
The default labeling is ‘-’
The character of labels attached to the same grid line is synchronized.
If you change the value of a label in a grid line, values of the other labels in the same grid line are automatically updated.
Note: However, when you modify a label attribute in the Properties palette, values of other labels in the same grid line are not updated automatically.
If you erase a label, other labels and their values are not affected.