How to keep a running total in php foreach loop

Question

I am trying to create a table that displays member data for three different types of members - it should display how many members were added each day, and then there needs to be a column that keeps a cumulative total month to date for the three different types of members. Example:

Members Added in March:

Date      Type A      Type A Total      Type B      Type B Total

1             23                23                   16                  16
2             13                36                   13                  29
3             16                52                   17                  46

My query looks like this:

$results=$wpdb->get_results("SELECT DAY(Subscription_Start_Date) as dayOfMonth, COUNT(a.user_id) as typeA, COUNT(b.user_id) as typeB, COUNT(c.user_id) as typeC
FROM users u
LEFT OUTER JOIN typeAUser a ON u.type_id = a.User_Id
LEFT OUTER JOIN typeBUser b ON u.type_id = b.User_Id
LEFT OUTER JOIN typeCUser c ON u.type_id = c.user_Id AND c.phone_opt_out != '1'
WHERE MONTH(Subscription_Start_Date) = MONTH(curdate()) AND YEAR(Subscription_Start_Date) = YEAR(curdate())
GROUP BY DAY(Subscription_Start_Date)
ORDER BY DAY(Subscription_Start_Date)");

I am outputting the data into a table using a foreach loop like so:

$resultTable = "<table><thead>
        <tr><td colspan='7'>Month to Date Members Added $currentMonth</td></tr>
        <tr>
        <th>Day of the Month</th>
        <th>Type A</th>
        <th>Type A Month to Date</th>
        <th>Type B</th>
        <th>Type B Month to Date</th>
        <th>Type C</th>
        <th>Type C Month to Date</th>
        </tr></thead><tbody>";

foreach($results as $r){
    $aMemPerDay = $r->typeA;
    $bMemPerDay = $r->typeB;
    $cMemPerDay = $r->typeC;

    $resultTable .= "<tr>
        <td>$r->dayOfMonth</td>
        <td>$aMemPerDay</td>
        <td>???</td>
        <td>$bMemPerDay</td>
        <td>???</td>
        <td>$cMemPerDay</td>
        <td>???</td>
        </tr>";
}
$resultTable .="</tbody></table>";

echo $resultTable;

The query returns the info I need for the number of members added per day, but I can't figure out how to keep a running total that increase each day. I have tried many things, but nothing seems to work. I tried implementing a variation of this solution within the foreach on each of the member types but when I put the $totalA variable into the table, it just printed out Array:

$totalA = array();
$runningSumA = 0;

foreach ($aMemPerDay as $aMem) {
    $runningSumA += $aMem;
    $totalA[] = $runningSum;
}

I even tried using a MySQL variable in the query (since there are only 30 days per month, I figured it wouldn't be overly cumbersome), but I wasn't able to get a cumulative result there either. I know that there is probably some manageable answer out there, but I can't seem to come up with it. Any direction would be appreciated!

Answer 1

$TotalA = 0;
$TotalB = 0;
$TotalC = 0;

foreach($results as $r){
    $aMemPerDay = $r->typeA;
    $bMemPerDay = $r->typeB;
    $cMemPerDay = $r->typeC;

    $TotalA += $aMemPerDay;
    $TotalB += $bMemPerDay;
    $TotalC += $bMemPerDay;

    $resultTable .= "<tr>
        <td>$r->dayOfMonth</td>
        <td>$aMemPerDay</td>
        <td>???</td>
        <td>$bMemPerDay</td>
        <td>???</td>
        <td>$cMemPerDay</td>
        <td>???</td>
        </tr>";
}