Aria for the Dead lute

Instrument

Item Details

Utility 45
Bonus Level 25
Dyeable No
Sellable Yes
Tradeable Yes

Restrictions

Level Required Any
Usable By
Minstrel

Magical Bonuses

Basic
Hit Points 28
Charisma 9
Spirit Resist 6%
Instruments 4

Raw Item JSON

{
  "sell_value" : 40056,
  "requirements" : {
    "usable_by" : [ 4 ]
  },
  "bonus_level" : 25,
  "sources" : {
    "monsters" : {
      "normal_drop" : [ "Smithy Olivan" ]
    }
  },
  "flags" : {
    "dyable" : false,
    "emblemizable" : false
  },
  "icon" : 2976,
  "utility" : 45.0,
  "delve_text" : "Realm: Albion\n \nUsable By: \n- Minstrel\n \nMagical Bonuses:\n- Instruments: 4 pts\n- Charisma: 9 pts\n- Spirit: 6%\n- Hits: 28 pts\n \n \n \nBonus Level: 25\n",
  "salvage_amount" : 18,
  "artifact" : false,
  "material" : 71,
  "name" : "Aria for the Dead lute",
  "usable_by" : [ 4 ],
  "realm" : 1,
  "id" : 16517,
  "category" : 4,
  "bonuses" : [ {
    "id" : 98,
    "type" : 2,
    "value" : 4
  }, {
    "id" : 7,
    "type" : 1,
    "value" : 9
  }, {
    "id" : 17,
    "type" : 5,
    "value" : 6
  }, {
    "type" : 4,
    "value" : 28
  } ],
  "ability_tags" : [ ]
}
How is utility calculated?