Go: 接種状況ダッシュボードのデータを使ってワクチン接種済者をカウントする

こちらで行ったのと同じ計算を Go で行いました。
Python3: 接種状況ダッシュボードのデータを使ってワクチン接種済者をカウントする

count_vaccination.go

// ----------------------------------------------------------------
//
//  count_vaccination.go
//
//                  Jan/26/2022
//
// ----------------------------------------------------------------
package main 

import (
    "fmt"
    "os"
    "log"
    "encoding/csv"
//  "reflect"
    "strconv"
    "time"
) 

// ----------------------------------------------------------------
func get_day_6months_proc () string {
    now := time.Now ()
    fmt.Printf ("%s\n" ,now)
    today := strconv.Itoa (now.Year()) + "-" +
        fmt.Sprintf ("%02d",now.Month()) + "-" +
        strconv.Itoa (now.Day())

    t3 := now.AddDate (0,0,-184)
    day_6months := strconv.Itoa (t3.Year()) + "-" +
        fmt.Sprintf ("%02d",t3.Month()) + "-" +
        strconv.Itoa (t3.Day())

    fmt.Println(today)
    fmt.Println(day_6months)

    return  day_6months
}

// ----------------------------------------------------------------
func count_proc(record [][]string,day_6months string){
    llx := len(record)

    second := 0
    second_6months := 0
    third := 0


    for it := 1; it < llx; it++{
        ss,_ := strconv.Atoi(record[it][2])
        second  += ss
        tt,_ := strconv.Atoi(record[it][3])
        third  += tt
        if (record[it][0] < day_6months){
            second_6months += ss
            }
    }

    fmt.Printf ("second = %d\n",second)
    fmt.Printf ("second_6months = %d\n",second_6months)
    fmt.Printf ("third = %d\n",third)
}


// ----------------------------------------------------------------
func main (){
    fmt.Fprintf (os.Stderr,"*** 開始 ***\n")

    file_csv := os.Args[1]
    fmt.Printf (file_csv + "\n")

    ff, err := os.Open(file_csv)
    if err != nil {
        log.Fatal(err)
    }

    rr := csv.NewReader(ff)

    record, err := rr.ReadAll()
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("%#v\n", len(record))
//  fmt.Println(reflect.TypeOf(record))

    day_6months := get_day_6months_proc()

    count_proc(record,day_6months)

    fmt.Fprintf (os.Stderr,"*** 終了 ***\n")
}

// ----------------------------------------------------------------

実行結果

$ go run count_vaccination.go summary_by_date.csv
*** 開始 ***
summary_by_date.csv
290
2022-01-26 19:50:18.261192179 +0900 JST m=+0.000425766
2022-01-26
2021-07-26
second = 93846301
second_6months = 29646353
third = 2892327
*** 終了 ***