<a href='available_symbols.html'>available_symbols()</a></code> to see available symbols.</p></td>
    </tr>
    <tr>
      <th>start_date</th>
      <td><p>character string.
Starting date for results in the format <code>"yyyy-mm-dd"</code> or <code>"yyyy-mm-dd hh-mm-ss"</code>.</p></td>
    </tr>
    <tr>
      <th>end_date</th>
      <td><p>character string.
Ending date for results in the format <code>"yyyy-mm-dd"</code> or <code>"yyyy-mm-dd hh-mm-ss"</code>.</p></td>
    </tr>
    <tr>
      <th>filter</