$month = $idx;
// Append leading zero
- if ($idx < 10) $month = 0 . $idx;
+ if ($idx < 10) $month = '0' . $idx;
// Count months
$months[$month] = countSumTotalData(bigintval($month), 'user_data', 'userid', 'birth_month', true, " AND `status`='CONFIRMED'");