my $color_num = 1;
while( @data = $query->fetchrow ) {

$rowcolor = 'RED';
if ($color_num % 2 > 0)
  {
   $rowcolor = 'GREEN';
  }
  
print REPORT_FILE qq(
    <tr  bgcolor=\"$rowcolor\">
    <td width=400 align=left>$data[0]</td>
        <td width=50 align=left>$data[1]</td>
        <td width=50 align=left>$data[2]</td>
        <td width=50 align=left>$data[3]</td>
        <td width=50 align=left>$data[4]</td>
        </tr>   )   
 $color_num++;
}