如何从表中对分组值求和？ 例如，我将这个名字加起来？

How do I sum grouped values from a table? For example I will sum the name?

this values :

2.997,
7.497

return : result!

I already have a function which delivers the whole sum this works fine. But I have don't a clue how to solve this problem ![enter image description here][1]

here is my function for the whole sum!

function calculateSum() {
    var sum = 0;
    $(".overviewTaxes").each(function() {
        var value = $(this).text();
        // add only if the value is number
        if(!isNaN(value) && value.length != 0) {
            sum += parseFloat(value);
        }
    });
    $( ".globalTaxSum" ).html(sum);
}


<tbody>
   <?php foreach ($overviews as $overview): ?>
      <tr>
         <td >
            <?php echo $overview["forename"] . " " . $overview["surname"]; ?>
         </td>
         <td>
            <?php echo $overview["article"]; ?>
         </td>
         <td>
            <?php echo $overview["articleprice"]; ?>
         </td>
         <td class="overviewTaxes">
            <?php

               $ps = $overview["articleprice"] * 0.3; //flat rate
               echo round($ps, 3) ;
            ?><br/>
         </td>
      </tr>
   <?php endforeach; ?>
</tbody>

Thanks for help.

Best regards
Marc Kevin