현재 아래와 같이 뽑았는데요..

월별환불은 데이터를 뽑아오지 못하네요... 0으로 나와버리는 상황입니다.

wr_255값도 월별로 뽑아야 하거든요..

코드는 다음과 같습니다. 어떻게 고쳐야 월별환불 칸에 나올까요?

<?php
$sub_menu = "200830";
include_once('./_common.php');

auth_check($auth[$sub_menu], 'r');

$g5['title'] = '월별 실적';
include_once('./member_count.sub.php');

$colspan = 6;

$max = 0;
$sum_total = 0;
$sql = " select SUBSTRING(wr_datetime,1,7) as vs_month, sum(wr_8) as total, sum(wr_255) as refund
            from g5_write_admin
            where date(wr_datetime) between '{$fr_date}' and '{$to_date}'
            group by vs_month
            order by vs_month desc";

$result = sql_query($sql);
for ($i=0; $row=sql_fetch_array($result); $i++) {
    $arr[$row['vs_month']] = $row['total'];

    if ($row['total'] > $max) $max = $row['total'];

    $sum_count += $row['total'];

    $sum_refund += $row['refund'];

}

?>

<div class="tbl_head01 tbl_wrap">
    <table>
    <caption><?php echo $g5['title']; ?> 목록</caption>
    <thead>
    <tr>
        <th scope="col">년-월</th>
        <th scope="col">그래프</th>
        <th scope="col">월별입금</th>
        <th scope="col">월별환불</th>
        <th scope="col">월별실적</th>

        <th scope="col">비율(%)</th>
    </tr>
    </thead>
    <tfoot>
    <tr>
        <td colspan="2">총계</td>
        <td><strong><?php echo number_format($sum_count) ?></strong></td>
        <td><?php echo number_format($sum_refund) ?></td>
        <td></td>
        </td></td>
        <td>100%</td>

    </tr>

    </tfoot>
    <tbody>
    <?php
    $i = 0;
    $k = 0;
    $save_count = -1;
    $tot_count = 0;
    if (count($arr)) {
        foreach ($arr as $key=>$value) {
            $count = $value;

            $rate = ($count / $sum_count * 100);
            $s_rate = number_format($rate, 1);

            $bg = 'bg'.($i%2);

    ?>

    <tr class="<?php echo $bg; ?>">
        <td class="td_category"><a href="./visit_date.php?fr_date=<?php echo $key ?>-01&to_date=<?php echo $key ?>-31"><?php echo $key ?></a></td>
        <td>
            <div class="visit_bar">
                <span style="width:<?php echo $s_rate ?>%"></span>
            </div>
        </td>

        <td class="td_numbig"><?php echo number_format($value) ?></td>

        <td class="td_numbig"><?php echo number_format($row[refund]) ?></td>
        <td class="td_numbig"></td>

        <td class="td_num"><?php echo $s_rate ?></td>
    </tr>

    <?php
        }

    } else {
        echo '<tr><td colspan="'.$colspan.'" class="empty_table">자료가 없습니다.</td></tr>';
    }
    ?>

    </tbody>
    </table>
</div>

<?php
include_once('./admin.tail.php');
?>