I have 2 aggregation in my query for Dau, Mau. how to combine them to find the ratio. have tried with bucket_script, scripted metric. nothing works,

[Dev_Profile]

Below is my query. is there any way to access multi-buckets value to manipulate n return the results.

{
  "_source": false,
  "aggs": {
    "nested_dau": {
      "nested": {
        "path": "dau"
      },
      "aggs": {
        "group_by_month": {
          "date_histogram": {
            "field": "dau.date",
            "calendar_interval": "month"
          },
          "aggs": {
            "sum_loggedin_users": {
              "sum": {
                "field": "dau.loggedinusers"
              }
            }
          }
        },
        "group_by_day": {
          "date_histogram": {
            "field": "dau.date",
            "calendar_interval": "day"
          },
          "aggs": {
            "sum_loggedin_users": {
              "sum": {
                "field": "dau.loggedinusers"
              }
            }
          }
        }
      }
    }
  }
}

[PodarcisMuralis (Murat K.)]

Maybe?

{
  "_source": false,
  "aggs": {
    "nested_dau": {
      "nested": {
        "path": "dau"
      },
      "aggs": {
        "group_by_month": {
          "date_histogram": {
            "field": "dau.date",
            "calendar_interval": "month"
          },
          "aggs": {
            "sum_loggedin_users_month": {
              "sum": {
                "field": "dau.loggedinusers"
              }
            }
          }
        },
        "group_by_day": {
          "date_histogram": {
            "field": "dau.date",
            "calendar_interval": "day"
          },
          "aggs": {
            "sum_loggedin_users_day": {
              "sum": {
                "field": "dau.loggedinusers"
              }
            }
          }
        },
        "ratio": {
          "bucket_selector": {
            "buckets_path": {
              "sumLoggedInMonth": "group_by_month>sum_loggedin_users_month",
              "sumLoggedInDay": "group_by_day>sum_loggedin_users_day"
            },
            "script": "params.sumLoggedInMonth / params.sumLoggedInDay"
          }
        }
      }
    }
  }
}

[Dev_Profile]

getting below exception. How to fix this ? TIA.

{
  "error": {
    "root_cause": [],
    "type": "search_phase_execution_exception",
    "reason": "",
    "phase": "fetch",
    "grouped": true,
    "failed_shards": [],
    "caused_by": {
      "type": "class_cast_exception",
      "reason": "class org.elasticsearch.search.aggregations.bucket.nested.InternalNested cannot be cast to class org.elasticsearch.search.aggregations.InternalMultiBucketAggregation (org.elasticsearch.search.aggregations.bucket.nested.InternalNested and org.elasticsearch.search.aggregations.InternalMultiBucketAggregation are in module org.elasticsearch.server@8.3.3 of loader 'app')"
    }
  },
  "status": 500
}