javascript : การตัดข้อมูลจาก array

  var sel_val = [['id','name','postal','phone', 'channel'],
                    ['','','','',''],
                    ['C-001', 'AAA','11130','+66123456','trade'],
                    ['วันที่','XX','XX','xx','xx'],
                    ['C-002','BBB','11110','+668123990','trade'],
                    ['D-003','CCC','10100','+6628865788','channel'],
                    ['D-004','DDD','10300','+6625572234','fleet'],
                    ['รวม','xx','xx','xx','xx'],
                    ['D-005','FFF','10200','+6623354500','fleet'],
                    ['D-006','GGG','10500','+6624466778','trade'],
                    ['รวม','xx','xx','xx','xx'],
                    ['C-007','HHH','14500','+025281800','channel']];
  const endofacc = sel_val.map(r => r[0]);
  console.log(endofacc.indexOf('รวม')); //  ans = 7.0 ได้ตัวแรกที่พบอันเดียว