If all members of data have 5 digits to use, the below formula should work. This will keep the first 5 characters from the right side of the data field member.
If the members don't all have 5 characters to keep, you can use a Custom Split in the data source pane. See the split on [Order ID].
Use the separator: -
Split off Last 1 columns
Hope that helps,
Try this Calculated Field.