Separate Multi-Select Text Fields on a Pie Chart

This is the way that I make a pie chart from a multi select field.

I create a child table representing each of the multi select choices which the user selected.

Then set up an automation that when the parent record is edited, to delete all the children and then to create a child record for every possible multi select choice, let's say there are 10 multi select choices so 10 children will be created, then the next step of the automation or pipeline will be to delete any of the children that were not actually selected.

 Then set up an automation that when the parent record is edited, to delete all the children and then to create a child record for every possible multi select choice, let's say there are 10 multi select choices so 10 children will be created, then the next step of the automation or pipeline will be to delete any of the children that were not actually selected. 

 Because the children are children of the parent, they can have a look up field to know which selections were made in the parent and then a formula field can determine for each child that was created whether or not it deserves to remain or needs to be deleted. By having the very first step of the automation delete any children, it ensures  that for any editing we are always starting with a clean slate.

Once you have the child table then it is very easy to make your pie charts off the child table