Creating categories based off my measure

Hi,

This is a two parter question. I have a measure calculating my how often my inventory is turning. I want however to be able to group these into categories "Less than one", "greater than two", etc.  Right now it doesnt seem to be grouping some of these correctly and i cant figure out why. From there i want to create a percentage of each of these categories but its not recognizing these groups unless i have another field in the table which defeats the purpose of trying to group these if i cant see how much inventory falls into each. Help!! 😞