Highlight a name in a dataset

Here’s an aesthetic issue I’m encountering after transforming a dataset.
I used Group By and Missing Value to create a row in the dataset that represents the average of the values. I am very happy with the result.
I am now at the visualization stage where I have two elements: a Bar Chart and a Table view, before sending this result as a PDF.
What I would like to do, and I don’t know if it’s possible, is to insert a color or change the character for “Mean” so that it is clearly distinguished as the average and not a name in the dataset.

If you have an idea …

Hello @Brain

Aiming to customize a table, take a look to the following post.