Dashboard column different color?

I added a new field to a dashboard and it’s a different color except when it has data.
What does that mean? I feel like it means something is wrong, but not sure what it might be.

In the picture below it’s the last column. Why is it shaded differently?

If I recall, that means the field is null.

Let’s see if someone else can confirm or not.

That would make a lot of sense in this case because I’m left joining the table the field comes from so I expect there to be nulls.

It’s the nulls that do that. If you don’t like that behavior, just display a calculated field that is ISNULL(value, ‘’). Then it will just show a blank when null and have the same color.