How to count the records and percentage
How to get the data of "chosen", "unchosen" and "percent"
Implement the percentage as a formula field with the following:
chosen / (chosen + 'not chosen') * 100
'not chosen' is don't work, How do I count the number of not chosen?
Are you always starting with the first left selection of the Multiple choice field? Is so, you can use this little hack.
Make sure the highest value is for the first selection, you can do this by dragging the values upwards like in the pic below.