Longest combined music duration per artist

.json

{
  "took" : 21,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "failed" : 0
  },
  "hits" : {
    "total" : 8392,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "per_artist" : {
      "doc_count_error_upper_bound" : -1,
      "sum_other_doc_count" : 7168,
      "buckets" : [ {
        "key" : "Nine Inch Nails",
        "doc_count" : 156,
        "total_duration" : {
          "value" : 38858.0
        }
      }, {
        "key" : "Muse",
        "doc_count" : 147,
        "total_duration" : {
          "value" : 37933.0
        }
      }, {
        "key" : "Nobuo Uematsu",
        "doc_count" : 166,
        "total_duration" : {
          "value" : 36001.0
        }
      }, {
        "key" : "Thrice",
        "doc_count" : 143,
        "total_duration" : {
          "value" : 33179.0
        }
      }, {
        "key" : "EZ3kiel",
        "doc_count" : 94,
        "total_duration" : {
          "value" : 28976.0
        }
      }, {
        "key" : "Slipknot",
        "doc_count" : 113,
        "total_duration" : {
          "value" : 28304.0
        }
      }, {
        "key" : "Foo Fighters",
        "doc_count" : 95,
        "total_duration" : {
          "value" : 25574.0
        }
      }, {
        "key" : "The Used",
        "doc_count" : 113,
        "total_duration" : {
          "value" : 25048.0
        }
      }, {
        "key" : "Disturbed",
        "doc_count" : 102,
        "total_duration" : {
          "value" : 24739.0
        }
      }, {
        "key" : "Korn",
        "doc_count" : 95,
        "total_duration" : {
          "value" : 24276.0
        }
      } ]
    }
  }
}