Restful Parsing for virtualServer status

Hi, i have some question about a json response, get from this endpoint '/mgmt/tm/ltm/virtual/stats'.

I tried to parse the output of the following endpoint(json) '/mgmt/tm/ltm/virtual/stats' in a test environment with successfull result: the output is easy to understand

{
    "entries": {
        "clientside.bitsIn": {
            "value": 0
        }
       ...
    }
}


In production, i got a different json. 
To keep it easy, in the following example,i replaced in the real link, partition/name with a generic string (~vippartition~vipname):

{ 
    "entries": {
        "https://localhost/mgmt/tm/ltm/virtual/~vippartition~vipname/~vippartition~vipname/stats": {
            "nestedStats": {
                "entries": {
                "clientside.bitsIn": {
                    "value": 0
                }
                ...
    }
}

The questions are: What's it? Why this difference in the structure of the json response?

Thank's at all