Table calculation using the calculated data on table

What is the problem or goal the end user is trying to solve or accomplish?

1. User is looking at doing table calculation to calculate the percentage

2. eg:

   1. Data:

      User_ID	Event
      1	Unlocks Door
      1	Opens Door
      1	Closes Door
      1	Locks Door
      2	Unlocks Door
      2	Opens Door
      3	Unlocks Door
      4	Unlocks Door
      1	Unlocks Door
      1	Opens Door

      
      

   2. User is trying to get the Count_Distinct(Opens Door) / Count_Distinct(Unlocks Door)

   
   

How are they solving it currently?

1. Proposing user to add a calculated column to calculate each Count_Distinct

What is the recommended solution by the Customer?

1. Ability to do table calculation on the chart itself