使用json.Unmarshal将http.Response转换为结构

I'm calling a remote API and getting a JSON response back. I'm trying to convert the *http.Response into a struct that I defined. Everything i've tried so far has resulted in an empty struct. Here is my attempt with json.Unmarshal

type Summary struct {
   Created  string  `json:"created"`          
   High     float64 `json:"high"`             
   Low      float64 `json:"low"`              
}

func getSummary() {

   url := "http://myurl"

   resp, err := http.Get(url)
   if err != nil {
       log.Fatalln(err)
   }

   body, err2 := ioutil.ReadAll(resp.Body)
   if err2 != nil {
       panic(err.Error())
   }

   log.Printf("body = %v", string(body))
   //outputs: {"success":true,"message":"","result":["High":0.43600000,"Low":0.43003737],"Created":"2017-06-25T03:06:46.83"}]}

   var summary = new(Summary)
   err3 := json.Unmarshal(body, &summary)
   if err3 != nil {
       fmt.Println("whoops:", err3)
       //outputs: whoops: <nil> 
   }

   log.Printf("s = %v", summary)
   //outputs: s = &{{0 0 0  0 0 0  0 0 0  0}}


}

What am I doing wrong? The JSON tags in my struct match the json keys from the response exactly...

edit: here is the JSON returned from the API

{
  "success": true,
  "message": "''",
  "result": [
    {
      "High": 0.0135,
      "Low": 0.012,
      "Created": "2014-02-13T00:00:00"
    }
  ]
}

edit i changed the struct to this but still not working

type Summary struct {
   Result struct {
       Created string  `json:"created"`
       High    float64 `json:"high"`
       Low     float64 `json:"low"`
   } 
 }