DataTables sort by numeric value and not string value

Hello,

I want to sort numeric value with html method, but it doesn't work. But, if I do the same with JS, it is word. Why ?

I use Datatables in HTML like this :

      <div  class="datatable">
  <table>
    <thead>
      <tr>
        <th class="th-sm">Name</th>
        <th class="th-sm">Position</th>
        <th class="th-sm">Office</th>
        <th class="th-sm">Age</th>
        <th class="th-sm">Start date</th>
        <th class="th-sm">Salary</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>Tiger Nixon</td>
        <td>System Architect</td>
        <td>Edinburgh</td>
        <td>61</td>
        <td>2011/04/25</td>
        <td>$320,800</td>
      </tr>
      <tr>
        <td>Ashton Cox</td>
        <td>Junior Technical Author</td>
        <td>San Francisco</td>
        <td>6</td>
        <td>2009/01/12</td>
        <td>$86,000</td>
      </tr>
      <tr>
        <td>Cedric Kelly</td>
        <td>Senior Javascript Developer</td>
        <td>Edinburgh</td>
        <td>22</td>
        <td>2012/03/29</td>
        <td>$433,060</td>
      </tr>
      <tr>
        <td>Rhona Davidson</td>
        <td>Integration Specialist</td>
        <td>Tokyo</td>
        <td>5</td>
        <td>2010/10/14</td>
        <td>$327,900</td>
      </tr>
    </tbody>
  </table>
</div>

and if I try with JS, I have correct sort

<script type="text/javascript">
  const basicData = {
  columns: ['Name', 'Position', 'Office', 'Age', 'Start date', 'Salary'],
  rows: [
    ["Tiger Nixon", "System Architect", "Edinburgh", 61, "2011/04/25", "$320,800"],
    ["Ashton Cox", "Junior Technical Author", "San Francisco", 6, "2009/01/12", "$86,000"],
    ["Cedric Kelly", "Senior Javascript Developer", "Edinburgh", 22, "2012/03/29", "$433,060"],
    ["Rhona Davidson", "Integration Specialist", "Tokyo", 5, "2010/10/14", "$327,900"],
  ],
};

new mdb.Datatable(document.getElementById('datatable'), basicData)
</script>