When editing a table in a report, the spacing on the columns will adjust automatically to best distribute text and gaps in the table.
This is usually a good thing and will result in a table that presents information without having large gaps of empty space.
There are situations, however, where this may not be the behaviour you want. To enable maximum control, you can edit the table properties and enter the CSS code below:
white-space: nowrap
The following video tutorial explains in detail how to do this.