indexOf return negative one with map [0]

indexOf returning -1 in below

  function myFunction() {
  var ss = SpreadsheetApp.getActiveSpreadsheet()
  var acivesheet = ss.getActiveSheet()
  var data = acivesheet.getRange(2,1,13,1).getValues();
  var newdata = data.map(function(r){ return r[0]; });
  Logger.log(newdata.indexOf("10014"));
}

one column starting from second row