The percentages represent to which extent a players fits into a particular category. This number is generated per category, and does not represent the dispersion over all the categories.
In other words: The system adds up the maximum amount of points that can be gained for a specific category and considers this to be a 100% score. Any other score is simply calculated in reference to this maximum and will result in a percentage anywhere between 0% and 100%.
You can hide the percentage under “Result page” in the menu of the assessment. However, you would need to be subscribed to the Business Owl plan at the minimum.