By terms grouped data show the same value in time series

So I am trying to show the size of multiple folders over time in a time series diagram.
The Data is formated like this:
"Folder": [ {"ID":1, "Path":"/boot", "Size_in_B":139174528 }, {"ID":2, "Path":"/bin", "Size_in_B":7 }]
I got the data grouped by their name saved in the Path field, but their size is not shown correctly as every folder is shown having the same size.

are they stored as an array in the document? In this case it won't work properly in Kibana. You would have to flatten your data, by having 1 document for each id in the array.