Pie chart's slice size supports only a few aggregations, but why?


I'm using kibana4 & 5alpha.
I found that I can select the pie chart's slice size only from "Count", "Sum" and "Unique count".
I would like to use other aggregations such as Average or Percentiles and so on.
Is it difficult to support other aggregations, or is the any workaround?

My index data are like this.


And when I split the slice by "Terms" aggregation of "path", the slice size must be Count (/items:3, /users:2) or Sum of duration (/items:450, /users:130) or Unique count.
I want to make the slice size "Average" of them (/items:150, /users:65)


That's a great question. I'm honestly not sure why pie charts don't support the other aggregations as well for slice sizes. I've opened an enhancement issue on GitHub, if you'd like to track it: https://github.com/elastic/kibana/issues/7914

I can't think of a workaround other than using another chart like a bar chart that does support average and other aggregations on the y-axis (equivalent of slice size in a pie chart).