Have a look my approach. Is that what you're looking for? Let me know If you've any query.
I've used your capacity measure on size to show your 0 items.
workbook (version 9.3) attached for your reference.
Color KPI 9.3.twbx 23.9 KB
This is perfect. How do you assign colors to the various levels. This worked for me but I now need to figure out how to assign colors to the various levels. I can see in your screenshot, you were able to do that.
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