require __DIR__."/mpdf-vendor/autoload.php";
use Mpdf\Mpdf;

$mpdf = new Mpdf();
$html = "<h3>Customer Holding Report</h3><table border=1 width=100%>
<tr><th>Month</th><th>Gas</th><th>Holding</th></tr>";

foreach($data as $r){
  $html.="<tr>
  <td>{$r['month']}</td>
  <td>{$r['gascode']}</td>
  <td>{$r['holding']}</td>
  </tr>";
}
$html.="</table>";

$mpdf->WriteHTML($html);
$mpdf->Output("holding.pdf","I"); // stream only