Graph does not display if have value 0 as output

[Nurul Ain]

                                                           function drawChart() {
var data = google.visualization.arrayToDataTable([
  ['WEEK', 'PPM RESULT'],
  <?php
while($row = sqlsrv_fetch_array( $stmt, SQLSRV_FETCH_ASSOC))  
  {  
   echo "['".$row["WorkWeek"]."', ".$row["result"]."],";  
  }  
  ?>

]);