Requesting help with calculating percentage of individual category

Hello Team,

I want to calculate % of individual category of the data - kindly see the image below:

In the above image distinct values of ID's where the date/time is before now have been grouped by a category dimension in data.

Wanted to understand how to calculate percentage of each section using GUI lets say:

  1. Extra Session - 7/358 - 0.019
  2. Understanding - 200/358 - 0.558
  3. Connecting - 100/358 - 0.279
  4. Communicating - 34/358 - 0.094
  5. Supporting - 17/358 - 0.047

Requirement is that I have to calculate the above using GUI.

Here 358 is the total of all categories.

Is there any way to achieve this using GUI?..thanks heap in advance.