Get the counts at each levels in a tree like document structure

Example data
{
"userName": "spyderman",
"phoneNumber": "123ertre67890",
"devicegroup": "Globe/India/Delhi/Parkstreet/building0/401B",
"address": "#complete address with postal codes",
},
{
"userName": "batman",
"phoneNumber": "12345fas890",
"devicegroup": "Globe/India/delhi/Parkstreet/building0/402B",
"address": "#complete address with postal codes",
},
{
"userName": "superman",
"phoneNumber": "123456asf0",
"devicegroup": "Globe/India/delhi/gandhistreet/building0/401A",
"address": "#complete address with postal codes",
},

I wish to get the counts at each level:
The documents will not be duplicated (generates one per user registration into the system)
output desired:

countries @global level

cities @ country level

buildings @ street level

users @ street level and # users @ building level

I was thinking to use path tokenizers but then not sure how i can get the counts in the way i desire. can someone guide in this regard.

Please don't post the same question more than once, it makes it harder for people to help.

Let's continue the discussion in Get the count in a tree like structure of items